Stabilize HLS playback timestamps

app-tv/src/main/java/hu/bbara/purefin/tv/player/TvPlayerScreen.kt

@@ -165,6 +165,7 @@ fun TvPlayerScreen(
                         }
                         Key.DirectionUp, Key.DirectionDown,
                         Key.DirectionCenter, Key.Enter -> {
+                            viewModel.togglePlayPause()
                             viewModel.showControls()
                             true
                         }

core/data/build.gradle.kts

@@ -49,4 +49,5 @@ dependencies {
     implementation(libs.androidx.navigation3.runtime)
     implementation(platform(libs.androidx.compose.bom))
     implementation(libs.androidx.compose.ui)
+    testImplementation(libs.junit)
 }

core/data/src/main/java/hu/bbara/purefin/core/data/client/AndroidDeviceProfile.kt

@@ -1,14 +1,20 @@
 package hu.bbara.purefin.core.data.client
 
 import android.content.Context
+import android.media.AudioAttributes as PlatformAudioAttributes
+import android.media.AudioFormat
 import android.media.AudioManager
+import android.media.AudioTrack
 import android.media.MediaCodecList
 import android.util.Log
 import org.jellyfin.sdk.model.api.DeviceProfile
 import org.jellyfin.sdk.model.api.DirectPlayProfile
 import org.jellyfin.sdk.model.api.DlnaProfileType
+import org.jellyfin.sdk.model.api.EncodingContext
+import org.jellyfin.sdk.model.api.MediaStreamProtocol
 import org.jellyfin.sdk.model.api.SubtitleDeliveryMethod
 import org.jellyfin.sdk.model.api.SubtitleProfile
+import org.jellyfin.sdk.model.api.TranscodingProfile
 
 /**
  * Creates a DeviceProfile for Android devices with proper codec support detection.
@@ -17,7 +23,9 @@ import org.jellyfin.sdk.model.api.SubtitleProfile
 object AndroidDeviceProfile {
 
     private const val TAG = "AndroidDeviceProfile"
-    private const val DEFAULT_MAX_AUDIO_CHANNELS = 8
+    private const val DEFAULT_MAX_AUDIO_CHANNELS = 2
+    private const val PROBE_SAMPLE_RATE = 48_000
+    private const val PROBE_ENCODING = AudioFormat.ENCODING_PCM_16BIT
 
     @Volatile
     private var cachedSnapshot: CapabilitySnapshot? = null
@@ -45,7 +53,7 @@ object AndroidDeviceProfile {
             Log.d(TAG, "Max audio channels: $maxAudioChannels")
 
             val snapshot = CapabilitySnapshot(
-                deviceProfile = buildDeviceProfile(audioCodecs, videoCodecs),
+                deviceProfile = createDeviceProfile(audioCodecs, videoCodecs, maxAudioChannels),
                 maxAudioChannels = maxAudioChannels
             )
             cachedSnapshot = snapshot
@@ -55,10 +63,13 @@ object AndroidDeviceProfile {
 
     fun create(context: Context): DeviceProfile = getSnapshot(context).deviceProfile
 
-    private fun buildDeviceProfile(
+    internal fun createDeviceProfile(
         audioCodecs: List<String>,
-        videoCodecs: List<String>
+        videoCodecs: List<String>,
+        maxAudioChannels: Int
     ): DeviceProfile {
+        val hlsOptions = HlsPlaybackStability.conservativeHlsOptions
+
         return DeviceProfile(
             name = "Android Media3",
             maxStaticBitrate = 100_000_000,
@@ -74,8 +85,24 @@ object AndroidDeviceProfile {
                 )
             ),
 
-            // Empty transcoding profiles - Jellyfin will use its defaults
-            transcodingProfiles = emptyList(),
+            // Explicit video transcoding support keeps Jellyfin 10.10/10.11 from
+            // returning sources that exist but are not marked usable for playback.
+            transcodingProfiles = listOf(
+                TranscodingProfile(
+                    container = "ts",
+                    type = DlnaProfileType.VIDEO,
+                    videoCodec = "h264",
+                    audioCodec = "aac",
+                    protocol = MediaStreamProtocol.HLS,
+                    context = EncodingContext.STREAMING,
+                    maxAudioChannels = maxAudioChannels.toString(),
+                    minSegments = hlsOptions.minSegments,
+                    segmentLength = hlsOptions.segmentLengthSeconds,
+                    breakOnNonKeyFrames = hlsOptions.breakOnNonKeyFrames,
+                    copyTimestamps = hlsOptions.copyTimestamps,
+                    conditions = emptyList()
+                )
+            ),
 
             codecProfiles = emptyList(),
 
@@ -196,7 +223,7 @@ object AndroidDeviceProfile {
         val audioManager = context.getSystemService(AudioManager::class.java) ?: return DEFAULT_MAX_AUDIO_CHANNELS
         return runCatching {
             val devices = audioManager.getDevices(AudioManager.GET_DEVICES_OUTPUTS)
-            val maxDeviceChannels = devices
+            val reportedMaxChannels = devices
                 .flatMap { device ->
                     buildList {
                         addAll(device.channelCounts.toList())
@@ -205,15 +232,67 @@ object AndroidDeviceProfile {
                     }
                 }
                 .maxOrNull()
-
-            maxDeviceChannels
                 ?.takeIf { it > 0 }
                 ?: DEFAULT_MAX_AUDIO_CHANNELS
+
+            val verifiedMaxChannels = verifyOutputChannelSupport(reportedMaxChannels)
+            Log.d(TAG, "Reported max audio channels: $reportedMaxChannels, verified: $verifiedMaxChannels")
+            verifiedMaxChannels
         }.getOrElse {
             DEFAULT_MAX_AUDIO_CHANNELS
         }
     }
 
+    private fun verifyOutputChannelSupport(reportedMaxChannels: Int): Int {
+        val candidates = buildList {
+            if (reportedMaxChannels >= 8) add(8)
+            if (reportedMaxChannels >= 6) add(6)
+            add(2)
+        }.distinct()
+
+        return candidates.firstOrNull(::canCreateAudioTrackForChannelCount) ?: DEFAULT_MAX_AUDIO_CHANNELS
+    }
+
+    private fun canCreateAudioTrackForChannelCount(channelCount: Int): Boolean {
+        val channelMask = when (channelCount) {
+            8 -> AudioFormat.CHANNEL_OUT_7POINT1_SURROUND
+            6 -> AudioFormat.CHANNEL_OUT_5POINT1
+            2 -> AudioFormat.CHANNEL_OUT_STEREO
+            else -> return false
+        }
+
+        val minBufferSize = AudioTrack.getMinBufferSize(PROBE_SAMPLE_RATE, channelMask, PROBE_ENCODING)
+        if (minBufferSize <= 0) {
+            return false
+        }
+
+        return runCatching {
+            val audioTrack = AudioTrack.Builder()
+                .setAudioAttributes(
+                    PlatformAudioAttributes.Builder()
+                        .setUsage(PlatformAudioAttributes.USAGE_MEDIA)
+                        .setContentType(PlatformAudioAttributes.CONTENT_TYPE_MOVIE)
+                        .build()
+                )
+                .setAudioFormat(
+                    AudioFormat.Builder()
+                        .setSampleRate(PROBE_SAMPLE_RATE)
+                        .setEncoding(PROBE_ENCODING)
+                        .setChannelMask(channelMask)
+                        .build()
+                )
+                .setTransferMode(AudioTrack.MODE_STREAM)
+                .setBufferSizeInBytes(minBufferSize * 2)
+                .build()
+
+            try {
+                audioTrack.state == AudioTrack.STATE_INITIALIZED
+            } finally {
+                audioTrack.release()
+            }
+        }.getOrElse { false }
+    }
+
     private fun channelMaskToCount(mask: Int): Int {
         return if (mask == 0) {
             0

core/data/src/main/java/hu/bbara/purefin/core/data/client/HlsPlaybackStability.kt

@@ -0,0 +1,17 @@
+package hu.bbara.purefin.core.data.client
+
+internal data class HlsStabilityOptions(
+    val segmentLengthSeconds: Int,
+    val minSegments: Int,
+    val breakOnNonKeyFrames: Boolean,
+    val copyTimestamps: Boolean
+)
+
+internal object HlsPlaybackStability {
+    val conservativeHlsOptions = HlsStabilityOptions(
+        segmentLengthSeconds = 6,
+        minSegments = 3,
+        breakOnNonKeyFrames = false,
+        copyTimestamps = true
+    )
+}

core/data/src/main/java/hu/bbara/purefin/core/data/client/JellyfinApiClient.kt

@@ -50,6 +50,14 @@ class JellyfinApiClient @Inject constructor(
     companion object {
         private const val TAG = "JellyfinApiClient"
         private const val MAX_STREAMING_BITRATE = 100_000_000
+
+        internal fun streamingHlsOptionsFor(
+            urlStrategy: PlaybackSourcePlanner.UrlStrategy
+        ): HlsStabilityOptions? = when (urlStrategy) {
+            PlaybackSourcePlanner.UrlStrategy.DIRECT_PLAY -> null
+            PlaybackSourcePlanner.UrlStrategy.DIRECT_STREAM,
+            PlaybackSourcePlanner.UrlStrategy.TRANSCODE -> HlsPlaybackStability.conservativeHlsOptions
+        }
     }
 
     private val jellyfin = createJellyfin {
@@ -281,76 +289,32 @@ class JellyfinApiClient @Inject constructor(
     suspend fun getPlaybackDecision(mediaId: UUID, forceTranscode: Boolean = false): PlaybackDecision? = withContext(Dispatchers.IO) {
         val playbackInfo = requestPlaybackInfo(mediaId, forceTranscode) ?: return@withContext null
         val capabilitySnapshot = AndroidDeviceProfile.getSnapshot(applicationContext)
-        val selectedMediaSource = selectMediaSource(playbackInfo.mediaSources, forceTranscode) ?: return@withContext null
+        val playbackPlan = PlaybackSourcePlanner.plan(playbackInfo.mediaSources, forceTranscode) ?: return@withContext null
+        val selectedMediaSource = playbackPlan.mediaSource
 
-        val url = when {
-            forceTranscode && selectedMediaSource.supportsTranscoding -> {
-                resolveTranscodeUrl(
-                    mediaId = mediaId,
-                    mediaSource = selectedMediaSource,
-                    playSessionId = playbackInfo.playSessionId,
-                    maxAudioChannels = capabilitySnapshot.maxAudioChannels
-                )
-            }
-
-            !forceTranscode && selectedMediaSource.supportsDirectPlay -> {
-                api.videosApi.getVideoStreamUrl(
-                    itemId = mediaId,
-                    static = true,
-                    mediaSourceId = selectedMediaSource.id,
-                    playSessionId = playbackInfo.playSessionId,
-                    liveStreamId = selectedMediaSource.liveStreamId
-                )
-            }
-
-            !forceTranscode && selectedMediaSource.supportsDirectStream -> {
-                api.videosApi.getVideoStreamUrl(
-                    itemId = mediaId,
-                    static = false,
-                    mediaSourceId = selectedMediaSource.id,
-                    playSessionId = playbackInfo.playSessionId,
-                    liveStreamId = selectedMediaSource.liveStreamId,
-                    container = selectedMediaSource.transcodingContainer ?: selectedMediaSource.container,
-                    enableAutoStreamCopy = true,
-                    allowVideoStreamCopy = true,
-                    allowAudioStreamCopy = true,
-                    maxAudioChannels = capabilitySnapshot.maxAudioChannels
-                )
-            }
-
-            selectedMediaSource.supportsTranscoding -> {
-                resolveTranscodeUrl(
-                    mediaId = mediaId,
-                    mediaSource = selectedMediaSource,
-                    playSessionId = playbackInfo.playSessionId,
-                    maxAudioChannels = capabilitySnapshot.maxAudioChannels
-                )
-            }
-
-            else -> null
-        } ?: return@withContext null
-
-        val playMethod = when {
-            forceTranscode -> PlayMethod.TRANSCODE
-            selectedMediaSource.supportsDirectPlay -> PlayMethod.DIRECT_PLAY
-            selectedMediaSource.supportsDirectStream -> PlayMethod.DIRECT_STREAM
-            selectedMediaSource.supportsTranscoding -> PlayMethod.TRANSCODE
-            else -> return@withContext null
-        }
+        val url = resolvePlaybackUrl(
+            mediaId = mediaId,
+            mediaSource = selectedMediaSource,
+            urlStrategy = playbackPlan.urlStrategy,
+            playSessionId = playbackInfo.playSessionId,
+            maxAudioChannels = capabilitySnapshot.maxAudioChannels
+        ) ?: return@withContext null
 
         val reportContext = PlaybackReportContext(
-            playMethod = playMethod,
+            playMethod = playbackPlan.playMethod,
             mediaSourceId = selectedMediaSource.id,
             audioStreamIndex = selectedMediaSource.defaultAudioStreamIndex,
             subtitleStreamIndex = selectedMediaSource.defaultSubtitleStreamIndex,
             liveStreamId = selectedMediaSource.liveStreamId,
             playSessionId = playbackInfo.playSessionId,
-            canRetryWithTranscoding = !forceTranscode &&
-                playMethod != PlayMethod.TRANSCODE &&
-                selectedMediaSource.supportsTranscoding
+            canRetryWithTranscoding = playbackPlan.canRetryWithTranscoding
         )
 
-        Log.d(TAG, "Playback decision for $mediaId: $playMethod using ${selectedMediaSource.id}")
+        Log.d(
+            TAG,
+            "Playback decision for $mediaId: ${playbackPlan.playMethod} using ${selectedMediaSource.id}" +
+                if (playbackPlan.usedFallback) " (conservative fallback)" else ""
+        )
         PlaybackDecision(
             url = url,
             mediaSource = selectedMediaSource,
@@ -365,37 +329,20 @@ class JellyfinApiClient @Inject constructor(
 
         val capabilitySnapshot = AndroidDeviceProfile.getSnapshot(applicationContext)
 
-        val url = when {
-            mediaSource.supportsDirectPlay -> api.videosApi.getVideoStreamUrl(
-                itemId = mediaId,
-                static = true,
-                mediaSourceId = mediaSource.id,
-                liveStreamId = mediaSource.liveStreamId
-            )
+        val playbackPlan = PlaybackSourcePlanner.plan(mediaSource) ?: return@withContext null
+        val url = resolvePlaybackUrl(
+            mediaId = mediaId,
+            mediaSource = playbackPlan.mediaSource,
+            urlStrategy = playbackPlan.urlStrategy,
+            playSessionId = null,
+            maxAudioChannels = capabilitySnapshot.maxAudioChannels
+        )
 
-            mediaSource.supportsDirectStream -> api.videosApi.getVideoStreamUrl(
-                itemId = mediaId,
-                static = false,
-                mediaSourceId = mediaSource.id,
-                liveStreamId = mediaSource.liveStreamId,
-                container = mediaSource.transcodingContainer ?: mediaSource.container,
-                enableAutoStreamCopy = true,
-                allowVideoStreamCopy = true,
-                allowAudioStreamCopy = true,
-                maxAudioChannels = capabilitySnapshot.maxAudioChannels
-            )
-
-            mediaSource.supportsTranscoding -> resolveTranscodeUrl(
-                mediaId = mediaId,
-                mediaSource = mediaSource,
-                playSessionId = null,
-                maxAudioChannels = capabilitySnapshot.maxAudioChannels
-            )
-
-            else -> null
-        }
-
-        Log.d(TAG, "Resolved standalone playback URL for $mediaId -> $url")
+        Log.d(
+            TAG,
+            "Resolved standalone playback URL for $mediaId -> $url via ${playbackPlan.playMethod}" +
+                if (playbackPlan.usedFallback) " (conservative fallback)" else ""
+        )
         url
     }
 
@@ -466,6 +413,11 @@ class JellyfinApiClient @Inject constructor(
         }
 
         val capabilitySnapshot = AndroidDeviceProfile.getSnapshot(applicationContext)
+        Log.d(
+            TAG,
+            "Playback request for $mediaId (forceTranscode=$forceTranscode) maxAudioChannels=${capabilitySnapshot.maxAudioChannels}, " +
+                "hlsOptions=${HlsPlaybackStability.conservativeHlsOptions}"
+        )
         val response = api.mediaInfoApi.getPostedPlaybackInfo(
             mediaId,
             PlaybackInfoDto(
@@ -482,27 +434,93 @@ class JellyfinApiClient @Inject constructor(
             )
         )
 
-        Log.d(TAG, "PlaybackInfo for $mediaId -> sources=${response.content.mediaSources.size}, session=${response.content.playSessionId}")
+        logPlaybackInfo(
+            mediaId = mediaId,
+            playbackInfo = response.content,
+            forceTranscode = forceTranscode
+        )
         return response.content
     }
 
-    private fun selectMediaSource(mediaSources: List<MediaSourceInfo>, forceTranscode: Boolean): MediaSourceInfo? {
-        return when {
-            forceTranscode -> mediaSources.firstOrNull { it.supportsTranscoding }
-            else -> mediaSources.firstOrNull { it.supportsDirectPlay }
-                ?: mediaSources.firstOrNull { it.supportsDirectStream }
-                ?: mediaSources.firstOrNull { it.supportsTranscoding }
-                ?: mediaSources.firstOrNull()
+    private suspend fun resolvePlaybackUrl(
+        mediaId: UUID,
+        mediaSource: MediaSourceInfo,
+        urlStrategy: PlaybackSourcePlanner.UrlStrategy,
+        playSessionId: String?,
+        maxAudioChannels: Int
+    ): String? {
+        return when (urlStrategy) {
+            PlaybackSourcePlanner.UrlStrategy.DIRECT_PLAY -> api.videosApi.getVideoStreamUrl(
+                itemId = mediaId,
+                static = true,
+                mediaSourceId = mediaSource.id,
+                playSessionId = playSessionId,
+                liveStreamId = mediaSource.liveStreamId
+            )
+
+            PlaybackSourcePlanner.UrlStrategy.DIRECT_STREAM -> resolveDirectStreamUrl(
+                mediaId = mediaId,
+                mediaSource = mediaSource,
+                playSessionId = playSessionId,
+                maxAudioChannels = maxAudioChannels
+            )
+
+            PlaybackSourcePlanner.UrlStrategy.TRANSCODE -> resolveTranscodeUrl(
+                mediaId = mediaId,
+                mediaSource = mediaSource,
+                playSessionId = playSessionId,
+                maxAudioChannels = maxAudioChannels
+            )
         }
     }
 
+    private suspend fun resolveDirectStreamUrl(
+        mediaId: UUID,
+        mediaSource: MediaSourceInfo,
+        playSessionId: String?,
+        maxAudioChannels: Int
+    ): String {
+        val hlsOptions = streamingHlsOptionsFor(PlaybackSourcePlanner.UrlStrategy.DIRECT_STREAM)
+            ?: error("Direct stream requests must use HLS stability options.")
+
+        Log.d(
+            TAG,
+            "Stream URL request for $mediaId strategy=DIRECT_STREAM container=${mediaSource.transcodingContainer ?: mediaSource.container}, " +
+                "hlsOptions=$hlsOptions"
+        )
+        return api.videosApi.getVideoStreamUrl(
+            itemId = mediaId,
+            static = false,
+            mediaSourceId = mediaSource.id,
+            playSessionId = playSessionId,
+            liveStreamId = mediaSource.liveStreamId,
+            container = mediaSource.transcodingContainer ?: mediaSource.container,
+            segmentLength = hlsOptions.segmentLengthSeconds,
+            minSegments = hlsOptions.minSegments,
+            enableAutoStreamCopy = true,
+            allowVideoStreamCopy = true,
+            allowAudioStreamCopy = true,
+            breakOnNonKeyFrames = hlsOptions.breakOnNonKeyFrames,
+            copyTimestamps = hlsOptions.copyTimestamps,
+            maxAudioChannels = maxAudioChannels
+        )
+    }
+
     private suspend fun resolveTranscodeUrl(
         mediaId: UUID,
         mediaSource: MediaSourceInfo,
         playSessionId: String?,
         maxAudioChannels: Int
     ): String? {
+        val hlsOptions = streamingHlsOptionsFor(PlaybackSourcePlanner.UrlStrategy.TRANSCODE)
+            ?: error("Transcode requests must use HLS stability options.")
+
         mediaSource.transcodingUrl?.takeIf { it.isNotBlank() }?.let { transcodingUrl ->
+            Log.d(
+                TAG,
+                "Using server transcodingUrl for $mediaId strategy=TRANSCODE container=${mediaSource.transcodingContainer ?: mediaSource.container}, " +
+                    "hlsOptions=$hlsOptions"
+            )
             if (transcodingUrl.startsWith("http", ignoreCase = true)) {
                 return transcodingUrl
             }
@@ -510,6 +528,11 @@ class JellyfinApiClient @Inject constructor(
             return "$baseUrl$transcodingUrl"
         }
 
+        Log.d(
+            TAG,
+            "Stream URL request for $mediaId strategy=TRANSCODE container=${mediaSource.transcodingContainer ?: mediaSource.container ?: "mp4"}, " +
+                "hlsOptions=$hlsOptions"
+        )
         return api.videosApi.getVideoStreamUrl(
             itemId = mediaId,
             static = false,
@@ -517,10 +540,38 @@ class JellyfinApiClient @Inject constructor(
             playSessionId = playSessionId,
             liveStreamId = mediaSource.liveStreamId,
             container = mediaSource.transcodingContainer ?: mediaSource.container ?: "mp4",
+            segmentLength = hlsOptions.segmentLengthSeconds,
+            minSegments = hlsOptions.minSegments,
             enableAutoStreamCopy = false,
             allowVideoStreamCopy = false,
             allowAudioStreamCopy = false,
+            breakOnNonKeyFrames = hlsOptions.breakOnNonKeyFrames,
+            copyTimestamps = hlsOptions.copyTimestamps,
             maxAudioChannels = maxAudioChannels
         )
     }
+
+    private fun logPlaybackInfo(
+        mediaId: UUID,
+        playbackInfo: PlaybackInfoResponse,
+        forceTranscode: Boolean
+    ) {
+        Log.d(
+            TAG,
+            "PlaybackInfo for $mediaId (forceTranscode=$forceTranscode) -> " +
+                "sources=${playbackInfo.mediaSources.size}, session=${playbackInfo.playSessionId}, error=${playbackInfo.errorCode}"
+        )
+
+        playbackInfo.mediaSources.forEachIndexed { index, mediaSource ->
+            Log.d(
+                TAG,
+                "PlaybackInfo[$index] id=${mediaSource.id}, container=${mediaSource.container}, " +
+                    "transcodingContainer=${mediaSource.transcodingContainer}, protocol=${mediaSource.protocol}, " +
+                    "supportsDirectPlay=${mediaSource.supportsDirectPlay}, " +
+                    "supportsDirectStream=${mediaSource.supportsDirectStream}, " +
+                    "supportsTranscoding=${mediaSource.supportsTranscoding}, " +
+                    "hasTranscodingUrl=${!mediaSource.transcodingUrl.isNullOrBlank()}"
+            )
+        }
+    }
 }

core/data/src/main/java/hu/bbara/purefin/core/data/client/PlaybackSourcePlanner.kt

@@ -0,0 +1,78 @@
+package hu.bbara.purefin.core.data.client
+
+import org.jellyfin.sdk.model.api.MediaSourceInfo
+import org.jellyfin.sdk.model.api.PlayMethod
+
+internal object PlaybackSourcePlanner {
+    data class Plan(
+        val mediaSource: MediaSourceInfo,
+        val urlStrategy: UrlStrategy,
+        val playMethod: PlayMethod,
+        val canRetryWithTranscoding: Boolean,
+        val usedFallback: Boolean
+    )
+
+    enum class UrlStrategy {
+        DIRECT_PLAY,
+        DIRECT_STREAM,
+        TRANSCODE
+    }
+
+    fun plan(mediaSources: List<MediaSourceInfo>, forceTranscode: Boolean): Plan? {
+        val selected = when {
+            forceTranscode -> mediaSources.firstOrNull { it.supportsTranscoding }?.let { mediaSource ->
+                PlannedSelection(
+                    mediaSource = mediaSource,
+                    urlStrategy = UrlStrategy.TRANSCODE,
+                    playMethod = PlayMethod.TRANSCODE
+                )
+            }
+
+            else -> mediaSources.firstOrNull { it.supportsDirectPlay }?.let { mediaSource ->
+                PlannedSelection(
+                    mediaSource = mediaSource,
+                    urlStrategy = UrlStrategy.DIRECT_PLAY,
+                    playMethod = PlayMethod.DIRECT_PLAY
+                )
+            } ?: mediaSources.firstOrNull { it.supportsDirectStream }?.let { mediaSource ->
+                PlannedSelection(
+                    mediaSource = mediaSource,
+                    urlStrategy = UrlStrategy.DIRECT_STREAM,
+                    playMethod = PlayMethod.DIRECT_STREAM
+                )
+            } ?: mediaSources.firstOrNull { it.supportsTranscoding }?.let { mediaSource ->
+                PlannedSelection(
+                    mediaSource = mediaSource,
+                    urlStrategy = UrlStrategy.TRANSCODE,
+                    playMethod = PlayMethod.TRANSCODE
+                )
+            } ?: mediaSources.firstOrNull()?.let { mediaSource ->
+                PlannedSelection(
+                    mediaSource = mediaSource,
+                    urlStrategy = UrlStrategy.DIRECT_STREAM,
+                    playMethod = PlayMethod.DIRECT_STREAM,
+                    usedFallback = true
+                )
+            }
+        } ?: return null
+
+        return Plan(
+            mediaSource = selected.mediaSource,
+            urlStrategy = selected.urlStrategy,
+            playMethod = selected.playMethod,
+            canRetryWithTranscoding = !forceTranscode &&
+                selected.playMethod != PlayMethod.TRANSCODE &&
+                mediaSources.any { it.supportsTranscoding },
+            usedFallback = selected.usedFallback
+        )
+    }
+
+    fun plan(mediaSource: MediaSourceInfo): Plan? = plan(listOf(mediaSource), forceTranscode = false)
+
+    private data class PlannedSelection(
+        val mediaSource: MediaSourceInfo,
+        val urlStrategy: UrlStrategy,
+        val playMethod: PlayMethod,
+        val usedFallback: Boolean = false
+    )
+}

core/data/src/test/java/hu/bbara/purefin/core/data/client/AndroidDeviceProfileTest.kt

@@ -0,0 +1,34 @@
+package hu.bbara.purefin.core.data.client
+
+import org.jellyfin.sdk.model.api.DlnaProfileType
+import org.jellyfin.sdk.model.api.EncodingContext
+import org.jellyfin.sdk.model.api.MediaStreamProtocol
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertTrue
+import org.junit.Test
+
+class AndroidDeviceProfileTest {
+    @Test
+    fun `device profile includes explicit video transcoding support`() {
+        val profile = AndroidDeviceProfile.createDeviceProfile(
+            audioCodecs = listOf("aac", "ac3"),
+            videoCodecs = listOf("h264", "hevc"),
+            maxAudioChannels = 6
+        )
+
+        val transcodingProfile = profile.transcodingProfiles.single()
+
+        assertEquals(DlnaProfileType.VIDEO, transcodingProfile.type)
+        assertEquals("ts", transcodingProfile.container)
+        assertEquals("h264", transcodingProfile.videoCodec)
+        assertEquals("aac", transcodingProfile.audioCodec)
+        assertEquals(MediaStreamProtocol.HLS, transcodingProfile.protocol)
+        assertEquals(EncodingContext.STREAMING, transcodingProfile.context)
+        assertEquals("6", transcodingProfile.maxAudioChannels)
+        assertEquals(3, transcodingProfile.minSegments)
+        assertEquals(6, transcodingProfile.segmentLength)
+        assertFalse(transcodingProfile.breakOnNonKeyFrames)
+        assertTrue(transcodingProfile.copyTimestamps)
+    }
+}

core/data/src/test/java/hu/bbara/purefin/core/data/client/JellyfinApiClientTest.kt

@@ -0,0 +1,29 @@
+package hu.bbara.purefin.core.data.client
+
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNull
+import org.junit.Test
+
+class JellyfinApiClientTest {
+    @Test
+    fun `direct play requests do not apply HLS stability options`() {
+        val options = JellyfinApiClient.streamingHlsOptionsFor(PlaybackSourcePlanner.UrlStrategy.DIRECT_PLAY)
+
+        assertNull(options)
+    }
+
+    @Test
+    fun `direct stream requests use conservative HLS stability options`() {
+        val options = JellyfinApiClient.streamingHlsOptionsFor(PlaybackSourcePlanner.UrlStrategy.DIRECT_STREAM)
+
+        assertEquals(HlsPlaybackStability.conservativeHlsOptions, options)
+    }
+
+    @Test
+    fun `transcode requests use the same HLS stability options as direct stream`() {
+        val directStreamOptions = JellyfinApiClient.streamingHlsOptionsFor(PlaybackSourcePlanner.UrlStrategy.DIRECT_STREAM)
+        val transcodeOptions = JellyfinApiClient.streamingHlsOptionsFor(PlaybackSourcePlanner.UrlStrategy.TRANSCODE)
+
+        assertEquals(directStreamOptions, transcodeOptions)
+    }
+}

core/data/src/test/java/hu/bbara/purefin/core/data/client/PlaybackSourcePlannerTest.kt

@@ -0,0 +1,111 @@
+package hu.bbara.purefin.core.data.client
+
+import org.jellyfin.sdk.model.api.MediaProtocol
+import org.jellyfin.sdk.model.api.MediaSourceInfo
+import org.jellyfin.sdk.model.api.MediaSourceType
+import org.jellyfin.sdk.model.api.MediaStreamProtocol
+import org.jellyfin.sdk.model.api.PlayMethod
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertNull
+import org.junit.Assert.assertSame
+import org.junit.Assert.assertTrue
+import org.junit.Test
+
+class PlaybackSourcePlannerTest {
+    @Test
+    fun `transcode-only source is selected for playback`() {
+        val mediaSource = mediaSource(id = "transcode-only", supportsTranscoding = true)
+
+        val plan = requireNotNull(
+            PlaybackSourcePlanner.plan(
+                mediaSources = listOf(mediaSource),
+                forceTranscode = false
+            )
+        )
+
+        assertSame(mediaSource, plan.mediaSource)
+        assertEquals(PlaybackSourcePlanner.UrlStrategy.TRANSCODE, plan.urlStrategy)
+        assertEquals(PlayMethod.TRANSCODE, plan.playMethod)
+        assertFalse(plan.canRetryWithTranscoding)
+        assertFalse(plan.usedFallback)
+    }
+
+    @Test
+    fun `first source falls back to direct stream when Jellyfin flags are inconsistent`() {
+        val mediaSource = mediaSource(id = "flagless")
+
+        val plan = requireNotNull(
+            PlaybackSourcePlanner.plan(
+                mediaSources = listOf(mediaSource),
+                forceTranscode = false
+            )
+        )
+
+        assertSame(mediaSource, plan.mediaSource)
+        assertEquals(PlaybackSourcePlanner.UrlStrategy.DIRECT_STREAM, plan.urlStrategy)
+        assertEquals(PlayMethod.DIRECT_STREAM, plan.playMethod)
+        assertFalse(plan.canRetryWithTranscoding)
+        assertTrue(plan.usedFallback)
+    }
+
+    @Test
+    fun `retry with transcoding stays enabled when another source can transcode`() {
+        val directPlaySource = mediaSource(id = "direct-play", supportsDirectPlay = true)
+        val transcodeSource = mediaSource(id = "transcode", supportsTranscoding = true)
+
+        val plan = requireNotNull(
+            PlaybackSourcePlanner.plan(
+                mediaSources = listOf(directPlaySource, transcodeSource),
+                forceTranscode = false
+            )
+        )
+
+        assertSame(directPlaySource, plan.mediaSource)
+        assertEquals(PlayMethod.DIRECT_PLAY, plan.playMethod)
+        assertTrue(plan.canRetryWithTranscoding)
+        assertFalse(plan.usedFallback)
+    }
+
+    @Test
+    fun `force transcode does not fall back to unusable source`() {
+        val mediaSource = mediaSource(id = "flagless")
+
+        val plan = PlaybackSourcePlanner.plan(
+            mediaSources = listOf(mediaSource),
+            forceTranscode = true
+        )
+
+        assertNull(plan)
+    }
+
+    private fun mediaSource(
+        id: String,
+        supportsDirectPlay: Boolean = false,
+        supportsDirectStream: Boolean = false,
+        supportsTranscoding: Boolean = false,
+        container: String? = "mkv"
+    ): MediaSourceInfo {
+        return MediaSourceInfo(
+            protocol = MediaProtocol.FILE,
+            id = id,
+            type = MediaSourceType.DEFAULT,
+            container = container,
+            isRemote = false,
+            readAtNativeFramerate = true,
+            ignoreDts = false,
+            ignoreIndex = false,
+            genPtsInput = false,
+            supportsTranscoding = supportsTranscoding,
+            supportsDirectStream = supportsDirectStream,
+            supportsDirectPlay = supportsDirectPlay,
+            isInfiniteStream = false,
+            requiresOpening = false,
+            requiresClosing = false,
+            requiresLooping = false,
+            supportsProbing = true,
+            transcodingSubProtocol = MediaStreamProtocol.HTTP,
+            hasSegments = false
+        )
+    }
+}

core/player/build.gradle.kts

@@ -34,6 +34,7 @@ dependencies {
     implementation(libs.hilt)
     ksp(libs.hilt.compiler)
     implementation(libs.medi3.exoplayer)
+    implementation(libs.medi3.exoplayer.hls)
     implementation(libs.media3.datasource.okhttp)
     implementation(libs.datastore)
     implementation(libs.kotlinx.serialization.json)

core/player/src/main/java/hu/bbara/purefin/core/player/manager/PendingSeekTracker.kt

@@ -0,0 +1,43 @@
+package hu.bbara.purefin.core.player.manager
+
+import kotlin.math.abs
+
+internal class PendingSeekTracker(
+    private val settleToleranceMs: Long = 500L
+) {
+    private var pendingSeek: PendingSeek? = null
+
+    fun currentPosition(playerPositionMs: Long): Long {
+        val pending = pendingSeek ?: return playerPositionMs
+        if (pending.isSatisfiedBy(playerPositionMs, settleToleranceMs)) {
+            pendingSeek = null
+            return playerPositionMs
+        }
+        return pending.targetPositionMs
+    }
+
+    fun recordSeek(basePositionMs: Long, targetPositionMs: Long): Long {
+        val target = targetPositionMs.coerceAtLeast(0L)
+        pendingSeek = PendingSeek(
+            targetPositionMs = target,
+            direction = target.compareTo(basePositionMs)
+        )
+        return target
+    }
+
+    fun clear() {
+        pendingSeek = null
+    }
+
+    private data class PendingSeek(
+        val targetPositionMs: Long,
+        val direction: Int
+    ) {
+        fun isSatisfiedBy(playerPositionMs: Long, settleToleranceMs: Long): Boolean =
+            when {
+                direction > 0 -> playerPositionMs >= targetPositionMs - settleToleranceMs
+                direction < 0 -> playerPositionMs <= targetPositionMs + settleToleranceMs
+                else -> abs(playerPositionMs - targetPositionMs) <= settleToleranceMs
+            }
+    }
+}

core/player/src/main/java/hu/bbara/purefin/core/player/manager/PlayerManager.kt

@@ -45,6 +45,7 @@ class PlayerManager @Inject constructor(
 ) {
 
     private val scope = CoroutineScope(SupervisorJob() + Dispatchers.Main.immediate)
+    private val pendingSeekTracker = PendingSeekTracker()
 
     private var currentMediaContext: MediaContext? = null
 
@@ -97,6 +98,7 @@ class PlayerManager @Inject constructor(
         }
 
         override fun onMediaItemTransition(mediaItem: MediaItem?, reason: Int) {
+            pendingSeekTracker.clear()
             refreshMetadata(mediaItem)
             refreshQueue()
         }
@@ -124,6 +126,7 @@ class PlayerManager @Inject constructor(
 
     fun play(mediaItem: MediaItem, mediaContext: MediaContext? = null, startPositionMs: Long? = null) {
         currentMediaContext = mediaContext
+        pendingSeekTracker.clear()
         if (startPositionMs != null) {
             player.setMediaItem(mediaItem, startPositionMs)
         } else {
@@ -139,6 +142,7 @@ class PlayerManager @Inject constructor(
 
     fun replaceCurrentMediaItem(mediaItem: MediaItem, mediaContext: MediaContext? = null, startPositionMs: Long? = null) {
         currentMediaContext = mediaContext
+        pendingSeekTracker.clear()
         val currentIndex = player.currentMediaItemIndex.takeIf { it != C.INDEX_UNSET } ?: run {
             play(mediaItem, mediaContext, startPositionMs)
             return
@@ -167,16 +171,17 @@ class PlayerManager @Inject constructor(
     }
 
     fun seekTo(positionMs: Long) {
-        player.seekTo(positionMs)
+        requestSeek(positionMs)
     }
 
     fun seekBy(deltaMs: Long) {
-        val target = (player.currentPosition + deltaMs).coerceAtLeast(0L)
-        seekTo(target)
+        val basePositionMs = pendingSeekTracker.currentPosition(player.currentPosition)
+        requestSeek(basePositionMs + deltaMs, basePositionMs)
     }
 
     fun seekToLiveEdge() {
         if (player.isCurrentMediaItemLive) {
+            pendingSeekTracker.clear()
             player.seekToDefaultPosition()
             player.play()
         }
@@ -184,12 +189,14 @@ class PlayerManager @Inject constructor(
 
     fun next() {
         if (player.hasNextMediaItem()) {
+            pendingSeekTracker.clear()
             player.seekToNextMediaItem()
         }
     }
 
     fun previous() {
         if (player.hasPreviousMediaItem()) {
+            pendingSeekTracker.clear()
             player.seekToPreviousMediaItem()
         }
     }
@@ -251,6 +258,7 @@ class PlayerManager @Inject constructor(
         val items = _queue.value
         val targetIndex = items.indexOfFirst { it.id == id }
         if (targetIndex >= 0) {
+            pendingSeekTracker.clear()
             player.seekToDefaultPosition(targetIndex)
             player.playWhenReady = true
             refreshQueue()
@@ -265,12 +273,31 @@ class PlayerManager @Inject constructor(
         val duration = player.duration.takeIf { it > 0 } ?: _progress.value.durationMs
         return PlaybackProgressSnapshot(
             durationMs = duration,
-            positionMs = player.currentPosition,
+            positionMs = pendingSeekTracker.currentPosition(player.currentPosition),
             bufferedMs = player.bufferedPosition,
             isLive = player.isCurrentMediaItemLive
         )
     }
 
+    private fun requestSeek(positionMs: Long, basePositionMs: Long = pendingSeekTracker.currentPosition(player.currentPosition)) {
+        val targetPositionMs = clampSeekPosition(positionMs)
+        pendingSeekTracker.recordSeek(basePositionMs = basePositionMs, targetPositionMs = targetPositionMs)
+        _progress.update {
+            it.copy(
+                durationMs = player.duration.takeIf { value -> value > 0L } ?: it.durationMs,
+                positionMs = targetPositionMs,
+                bufferedMs = player.bufferedPosition,
+                isLive = player.isCurrentMediaItemLive
+            )
+        }
+        player.seekTo(targetPositionMs)
+    }
+
+    private fun clampSeekPosition(positionMs: Long): Long {
+        val durationMs = player.duration.takeIf { it > 0L } ?: _progress.value.durationMs.takeIf { it > 0L }
+        return durationMs?.let { positionMs.coerceIn(0L, it) } ?: positionMs.coerceAtLeast(0L)
+    }
+
     private suspend fun applyTrackPreferences() {
         val context = currentMediaContext ?: return
         val preferences = trackPreferencesRepository.getMediaPreferences(context.preferenceKey).firstOrNull() ?: return

core/player/src/main/java/hu/bbara/purefin/core/player/module/VideoPlayerModule.kt

@@ -18,6 +18,7 @@ import dagger.Provides
 import dagger.hilt.InstallIn
 import dagger.hilt.android.components.ViewModelComponent
 import dagger.hilt.android.scopes.ViewModelScoped
+import hu.bbara.purefin.core.data.client.AndroidDeviceProfile
 
 @Module
 @InstallIn(ViewModelComponent::class)
@@ -27,6 +28,7 @@ object VideoPlayerModule {
     @Provides
     @ViewModelScoped
     fun provideVideoPlayer(application: Application, cacheDataSourceFactory: CacheDataSource.Factory): Player {
+        val capabilitySnapshot = AndroidDeviceProfile.getSnapshot(application)
         val trackSelector = DefaultTrackSelector(application)
         val audioAttributes =
             AudioAttributes.Builder()
@@ -37,7 +39,9 @@ object VideoPlayerModule {
         trackSelector.setParameters(
             trackSelector
                 .buildUponParameters()
-                .setTunnelingEnabled(true)
+                .setMaxAudioChannelCount(capabilitySnapshot.maxAudioChannels)
+                .setExceedAudioConstraintsIfNecessary(false)
+                .setTunnelingEnabled(false)
 //                .setPreferredAudioLanguage(
 //                    appPreferences.getValue(appPreferences.preferredAudioLanguage)
 //                )

core/player/src/main/java/hu/bbara/purefin/core/player/viewmodel/PlaybackRetryPolicy.kt

@@ -10,6 +10,10 @@ internal object PlaybackRetryPolicy {
     private val retryableErrorCodes = setOf(
         PlaybackException.ERROR_CODE_DECODER_INIT_FAILED,
         PlaybackException.ERROR_CODE_DECODER_QUERY_FAILED,
+        PlaybackException.ERROR_CODE_AUDIO_TRACK_INIT_FAILED,
+        PlaybackException.ERROR_CODE_AUDIO_TRACK_OFFLOAD_INIT_FAILED,
+        PlaybackException.ERROR_CODE_AUDIO_TRACK_WRITE_FAILED,
+        PlaybackException.ERROR_CODE_AUDIO_TRACK_OFFLOAD_WRITE_FAILED,
         PlaybackException.ERROR_CODE_PARSING_CONTAINER_MALFORMED,
         PlaybackException.ERROR_CODE_PARSING_CONTAINER_UNSUPPORTED
     )
@@ -45,6 +49,10 @@ internal object PlaybackRetryPolicy {
             }
         }.lowercase()
 
-        return "decoder" in detail || "codec" in detail || "unsupported" in detail
+        return "decoder" in detail ||
+            "codec" in detail ||
+            "unsupported" in detail ||
+            "audiotrack" in detail ||
+            "audio sink" in detail
     }
 }

core/player/src/test/java/hu/bbara/purefin/core/player/manager/PendingSeekTrackerTest.kt

@@ -0,0 +1,55 @@
+package hu.bbara.purefin.core.player.manager
+
+import org.junit.Assert.assertEquals
+import org.junit.Test
+
+class PendingSeekTrackerTest {
+
+    @Test
+    fun repeatedForwardSeeksAccumulateWhilePlayerPositionIsStale() {
+        val tracker = PendingSeekTracker()
+
+        val firstBase = tracker.currentPosition(playerPositionMs = 30_000L)
+        tracker.recordSeek(basePositionMs = firstBase, targetPositionMs = 40_000L)
+
+        val secondBase = tracker.currentPosition(playerPositionMs = 30_000L)
+        tracker.recordSeek(basePositionMs = secondBase, targetPositionMs = secondBase + 10_000L)
+
+        assertEquals(50_000L, tracker.currentPosition(playerPositionMs = 30_000L))
+    }
+
+    @Test
+    fun repeatedBackwardSeeksAccumulateWhilePlayerPositionIsStale() {
+        val tracker = PendingSeekTracker()
+
+        val firstBase = tracker.currentPosition(playerPositionMs = 30_000L)
+        tracker.recordSeek(basePositionMs = firstBase, targetPositionMs = 20_000L)
+
+        val secondBase = tracker.currentPosition(playerPositionMs = 30_000L)
+        tracker.recordSeek(basePositionMs = secondBase, targetPositionMs = secondBase - 10_000L)
+
+        assertEquals(10_000L, tracker.currentPosition(playerPositionMs = 30_000L))
+    }
+
+    @Test
+    fun pendingForwardSeekClearsOncePlayerCatchesUp() {
+        val tracker = PendingSeekTracker()
+
+        tracker.recordSeek(basePositionMs = 30_000L, targetPositionMs = 40_000L)
+
+        assertEquals(40_000L, tracker.currentPosition(playerPositionMs = 30_000L))
+        assertEquals(39_700L, tracker.currentPosition(playerPositionMs = 39_700L))
+        assertEquals(41_000L, tracker.currentPosition(playerPositionMs = 41_000L))
+    }
+
+    @Test
+    fun pendingBackwardSeekClearsOncePlayerCatchesUp() {
+        val tracker = PendingSeekTracker()
+
+        tracker.recordSeek(basePositionMs = 30_000L, targetPositionMs = 20_000L)
+
+        assertEquals(20_000L, tracker.currentPosition(playerPositionMs = 30_000L))
+        assertEquals(20_300L, tracker.currentPosition(playerPositionMs = 20_300L))
+        assertEquals(19_000L, tracker.currentPosition(playerPositionMs = 19_000L))
+    }
+}

core/player/src/test/java/hu/bbara/purefin/core/player/viewmodel/PlaybackRetryPolicyTest.kt

@@ -63,6 +63,22 @@ class PlaybackRetryPolicyTest {
         assertTrue(PlaybackRetryPolicy.shouldRetryWithTranscoding(error, playbackReportContext))
     }
 
+    @Test
+    fun `audio track init failures are retried when transcoding is available`() {
+        val error = PlayerError(
+            summary = "Playback error",
+            technicalDetail = "AudioTrack init failed",
+            source = PlayerErrorSource.PLAYBACK,
+            errorCode = PlaybackException.ERROR_CODE_AUDIO_TRACK_INIT_FAILED,
+            errorCodeName = "ERROR_CODE_AUDIO_TRACK_INIT_FAILED",
+            retryable = true
+        )
+
+        val playbackReportContext = playbackReportContext(playMethod = PlayMethod.DIRECT_PLAY)
+
+        assertTrue(PlaybackRetryPolicy.shouldRetryWithTranscoding(error, playbackReportContext))
+    }
+
     private fun playbackReportContext(playMethod: PlayMethod): PlaybackReportContext {
         return PlaybackReportContext(
             playMethod = playMethod,

gradle/libs.versions.toml

@@ -54,6 +54,7 @@ androidx-compose-foundation = { group = "androidx.compose.foundation", name = "f
 coil-compose = { group = "io.coil-kt.coil3", name = "coil-compose", version.ref = "coil" }
 coil-network-okhttp = { group = "io.coil-kt.coil3", name = "coil-network-okhttp", version.ref = "coil" }
 medi3-exoplayer = { group = "androidx.media3", name = "media3-exoplayer", version.ref = "media3"}
+medi3-exoplayer-hls = { group = "androidx.media3", name = "media3-exoplayer-hls", version.ref = "media3"}
 medi3-ui = { group = "androidx.media3", name = "media3-ui", version.ref = "media3"}
 medi3-ui-compose = { group = "androidx.media3", name = "media3-ui-compose-material3", version.ref = "media3"}
 medi3-ffmpeg-decoder = { group = "org.jellyfin.media3", name = "media3-ffmpeg-decoder", version.ref = "media3FfmpegDecoder"}