damontecres · darkflame91 · May 13, 2026
diff --git a/app/src/main/java/com/github/damontecres/wholphin/preferences/AppPreference.kt b/app/src/main/java/com/github/damontecres/wholphin/preferences/AppPreference.kt
@@ -391,7 +391,10 @@ sealed interface AppPreference<Pref, T> {
                 defaultValue = true,
                 getter = { it.playbackPreferences.overrides.ac3Supported },
                 setter = { prefs, value ->
-                    prefs.updatePlaybackOverrides { ac3Supported = value }
+                    prefs.updatePlaybackOverrides {
+                        ac3Supported = value
+                        if (!value) spdifArcSurroundAudio = false
+                    }
                 },
                 summaryOn = R.string.enabled,
                 summaryOff = R.string.disabled,
@@ -402,7 +405,10 @@ sealed interface AppPreference<Pref, T> {
                 defaultValue = false,
                 getter = { it.playbackPreferences.overrides.downmixStereo },
                 setter = { prefs, value ->
-                    prefs.updatePlaybackOverrides { downmixStereo = value }
+                    prefs.updatePlaybackOverrides {
+                        downmixStereo = value
+                        if (value) spdifArcSurroundAudio = false
+                    }
                 },
                 summaryOn = R.string.enabled,
                 summaryOff = R.string.disabled,
@@ -455,6 +461,28 @@ sealed interface AppPreference<Pref, T> {
                 summaryOff = R.string.disabled,
             )
 
+        val SpdifArcSurroundAudio =
+            AppSwitchPreference<AppPreferences>(
+                title = R.string.spdif_arc_surround_audio,
+                defaultValue = false,
+                getter = { it.playbackPreferences.overrides.spdifArcSurroundAudio },
+                setter = { prefs, value ->
+                    if (value) {
+                        prefs.updatePlaybackOverrides {
+                            spdifArcSurroundAudio = true
+                            ac3Supported = true
+                            downmixStereo = false
+                        }
+                    } else {
+                        prefs.updatePlaybackOverrides {
+                            spdifArcSurroundAudio = false
+                        }
+                    }
+                },
+                summaryOn = R.string.spdif_arc_surround_audio_summary_on,
+                summaryOff = R.string.spdif_arc_surround_audio_summary_off,
+            )
+
         val CinemaMode =
             AppSwitchPreference<AppPreferences>(
                 title = R.string.cinema_mode,
@@ -1108,6 +1136,7 @@ private val ExoPlayerSettings =
         AppPreference.FfmpegPreference,
         AppPreference.DownMixStereo,
         AppPreference.Ac3Supported,
+        AppPreference.SpdifArcSurroundAudio,
         AppPreference.AssSubtitleMode,
         AppPreference.DirectPlayPgs,
         AppPreference.DirectPlayDoviProfile7,

diff --git a/app/src/main/java/com/github/damontecres/wholphin/preferences/AppPreferencesSerializer.kt b/app/src/main/java/com/github/damontecres/wholphin/preferences/AppPreferencesSerializer.kt
@@ -68,6 +68,8 @@ class AppPreferencesSerializer
                                                 AppPreference.FfmpegPreference.defaultValue
                                             assPlaybackMode =
                                                 AppPreference.AssSubtitleMode.defaultValue
+                                            spdifArcSurroundAudio =
+                                                AppPreference.SpdifArcSurroundAudio.defaultValue
                                         }.build()
 
                                 mpvOptions =

diff --git a/app/src/main/java/com/github/damontecres/wholphin/services/DeviceProfileService.kt b/app/src/main/java/com/github/damontecres/wholphin/services/DeviceProfileService.kt
@@ -50,6 +50,7 @@ class DeviceProfileService
                             decodeAv1 = prefs.overrides.decodeAv1,
                             jellyfinTenEleven =
                                 serverVersion != null && serverVersion >= ServerVersion(10, 11, 0),
+                            spdifArcSurroundAudio = prefs.overrides.spdifArcSurroundAudio,
                         )
                     if (deviceProfile == null || this@DeviceProfileService.configuration != newConfig) {
                         this@DeviceProfileService.configuration = newConfig
@@ -64,6 +65,7 @@ class DeviceProfileService
                                 dolbyVisionELDirectPlay = newConfig.dolbyVisionELDirectPlay,
                                 decodeAv1 = prefs.overrides.decodeAv1,
                                 jellyfinTenEleven = newConfig.jellyfinTenEleven,
+                                spdifArcSurroundAudio = newConfig.spdifArcSurroundAudio,
                             )
                     }
                     this@DeviceProfileService.deviceProfile!!
@@ -83,4 +85,5 @@ data class DeviceProfileConfiguration(
     val dolbyVisionELDirectPlay: Boolean,
     val decodeAv1: Boolean,
     val jellyfinTenEleven: Boolean,
+    val spdifArcSurroundAudio: Boolean = false,
 )
diff --git a/app/src/main/java/com/github/damontecres/wholphin/services/MusicService.kt b/app/src/main/java/com/github/damontecres/wholphin/services/MusicService.kt
@@ -24,6 +24,7 @@ import com.github.damontecres.wholphin.util.BlockingList
 import com.github.damontecres.wholphin.util.LoadingState
 import com.github.damontecres.wholphin.util.PlaybackItemState
 import com.github.damontecres.wholphin.util.TrackActivityPlaybackListener
+import com.github.damontecres.wholphin.util.profile.Codec
 import com.github.damontecres.wholphin.util.profile.supportedAudioCodecs
 import dagger.hilt.android.qualifiers.ApplicationContext
 import kotlinx.coroutines.CoroutineScope
@@ -44,6 +45,7 @@ import org.jellyfin.sdk.api.client.extensions.universalAudioApi
 import org.jellyfin.sdk.api.sockets.subscribe
 import org.jellyfin.sdk.model.api.BaseItemKind
 import org.jellyfin.sdk.model.api.ImageType
+import org.jellyfin.sdk.model.api.MediaStreamType
 import org.jellyfin.sdk.model.api.PlayMethod
 import org.jellyfin.sdk.model.api.PlaystateCommand
 import org.jellyfin.sdk.model.api.PlaystateMessage
@@ -72,6 +74,7 @@ class MusicService
         private val playerFactory: PlayerFactory,
         private val serverRepository: ServerRepository,
         private val imageUrlService: ImageUrlService,
+        private val userPreferencesService: UserPreferencesService,
     ) {
         private val _state = MutableStateFlow(MusicServiceState.EMPTY)
         val state: StateFlow<MusicServiceState> = _state
@@ -198,7 +201,7 @@ class MusicService
             val mediaItems =
                 items
                     .filter { it.type == BaseItemKind.AUDIO }
-                    .map(::convert)
+                    .map { convert(it) }
             withContext(Dispatchers.Main) {
                 player.setMediaItems(mediaItems)
                 player.shuffleModeEnabled = shuffled
@@ -250,7 +253,7 @@ class MusicService
                                 list
                                     .getBlocking(it)
                                     ?.takeIf { it.type == BaseItemKind.AUDIO }
-                                    ?.let(::convert)
+                                    ?.let { convert(it) }
                             } else {
                                 Timber.v("Skipping $remaining")
                                 remaining--
@@ -266,12 +269,39 @@ class MusicService
         /**
          * Converts a [BaseItem] into a [MediaItem] setting an [AudioItem] as its tag
          */
-        private fun convert(audio: BaseItem): MediaItem {
+        private suspend fun convert(audio: BaseItem): MediaItem {
+            val spdifMode =
+                userPreferencesService
+                    .getCurrent()
+                    .appPreferences.playbackPreferences.overrides.spdifArcSurroundAudio
+
+            val needsAc3Transcode =
+                spdifMode &&
+                    audio.data.mediaSources
+                        ?.firstOrNull()
+                        ?.mediaStreams
+                        ?.any { stream ->
+                            stream.type == MediaStreamType.AUDIO &&
+                                (stream.channels ?: 0) > 2 &&
+                                stream.codec != Codec.Audio.AC3
+                        } ?: false
+
             val url =
-                api.universalAudioApi.getUniversalAudioStreamUrl(
-                    itemId = audio.id,
-                    container = audioFormats,
-                )
+                if (needsAc3Transcode) {
+                    api.universalAudioApi.getUniversalAudioStreamUrl(
+                        itemId = audio.id,
+                        container = listOf("mka"),
+                        transcodingContainer = "mka",
+                        maxAudioChannels = 6,
+                        transcodingAudioChannels = 6,
+                        audioCodec = Codec.Audio.AC3,
+                    )
+                } else {
+                    api.universalAudioApi.getUniversalAudioStreamUrl(
+                        itemId = audio.id,
+                        container = audioFormats,
+                    )
+                }
             Timber.i("url=%s", url)
             val imageUrl =
                 audio.data.albumId?.let { albumId ->

diff --git a/app/src/main/java/com/github/damontecres/wholphin/ui/playback/PlaybackViewModel.kt b/app/src/main/java/com/github/damontecres/wholphin/ui/playback/PlaybackViewModel.kt
@@ -55,6 +55,7 @@ import com.github.damontecres.wholphin.services.ScreensaverService
 import com.github.damontecres.wholphin.services.StreamChoiceService
 import com.github.damontecres.wholphin.services.UserPreferencesService
 import com.github.damontecres.wholphin.ui.formatBitrate
+import com.github.damontecres.wholphin.ui.gt
 import com.github.damontecres.wholphin.ui.isNotNullOrBlank
 import com.github.damontecres.wholphin.ui.launchDefault
 import com.github.damontecres.wholphin.ui.launchIO
@@ -653,7 +654,8 @@ class PlaybackViewModel
                                 } else {
                                     mpvDeviceProfile
                                 },
-                            maxAudioChannels = null,
+                            maxAudioChannels =
+                                if (preferences.appPreferences.playbackPreferences.overrides.spdifArcSurroundAudio) 6 else null,
                             audioStreamIndex = audioIndex,
                             subtitleStreamIndex = subtitleIndex,
                             mediaSourceId = currentItemPlayback.sourceId?.toServerString(),
@@ -844,12 +846,24 @@ class PlaybackViewModel
             userInitiated: Boolean,
         ): Boolean =
             withContext(Dispatchers.IO) {
-                // TODO there's probably no reason why we can't add external subtitles?
                 Timber.v("changeStreams direct play")
 
+                // Don't attempt DirectPlay if audio transcoding is required
+                if (preferences.appPreferences.playbackPreferences.overrides.spdifArcSurroundAudio && audioIndex != null) {
+                    currentPlayback.mediaSourceInfo.mediaStreams
+                        .orEmpty()
+                        .firstOrNull { it.index == audioIndex }
+                        ?.let {
+                            if (it.channels.gt(2) && it.codec != Codec.Audio.AC3) {
+                                return@withContext false
+                            }
+                        }
+                }
+
                 val source = currentPlayback.mediaSourceInfo
                 val externalSubtitle = source.findExternalSubtitle(subtitleIndex)
 
+                // TODO there's probably no reason why we can't add external subtitles?
                 if (externalSubtitle == null) {
                     val result =
                         withContext(Dispatchers.Main) {

diff --git a/app/src/main/java/com/github/damontecres/wholphin/util/profile/DeviceProfileUtils.kt b/app/src/main/java/com/github/damontecres/wholphin/util/profile/DeviceProfileUtils.kt
@@ -71,6 +71,7 @@ fun createDeviceProfile(
     dolbyVisionELDirectPlay: Boolean,
     decodeAv1: Boolean,
     jellyfinTenEleven: Boolean,
+    spdifArcSurroundAudio: Boolean = false,
 ) = buildDeviceProfile {
     val allowedAudioCodecs =
         when {
@@ -142,7 +143,11 @@ fun createDeviceProfile(
         if (supportsHevc) videoCodec(Codec.Video.HEVC)
         videoCodec(Codec.Video.H264)
 
-        audioCodec(*allowedAudioCodecs)
+        if (spdifArcSurroundAudio) {
+            audioCodec(Codec.Audio.AC3)
+        } else {
+            audioCodec(*allowedAudioCodecs)
+        }
 
         copyTimestamps = false
         enableSubtitlesInManifest = true
@@ -156,7 +161,11 @@ fun createDeviceProfile(
         container = Codec.Container.TS
         protocol = MediaStreamProtocol.HLS
 
-        audioCodec(Codec.Audio.AAC)
+        if (spdifArcSurroundAudio) {
+            audioCodec(Codec.Audio.AC3)
+        } else {
+            audioCodec(Codec.Audio.AAC)
+        }
     }
 
     // / Direct play profiles
@@ -415,6 +424,29 @@ fun createDeviceProfile(
         }
     }
 
+    // SPDIF/ARC mode: restrict non-AC3 multichannel audio to stereo
+    // to force server to transcode only multichannel to AC3
+    if (spdifArcSurroundAudio) {
+        supportedAudioCodecs
+            .filterNot { it == Codec.Audio.AC3 }
+            .forEach { audioCodec ->
+                codecProfile {
+                    type = CodecType.VIDEO_AUDIO
+                    codec = audioCodec
+                    conditions {
+                        ProfileConditionValue.AUDIO_CHANNELS lowerThanOrEquals 2
+                    }
+                }
+                codecProfile {
+                    type = CodecType.AUDIO
+                    codec = audioCodec
+                    conditions {
+                        ProfileConditionValue.AUDIO_CHANNELS lowerThanOrEquals 2
+                    }
+                }
+            }
+    }
+
     // / HDR exclude list
 
     // TODO Use VideoRangeType enum with Jellyfin 10.11 based SDK
@@ -522,7 +554,12 @@ fun createDeviceProfile(
         type = CodecType.VIDEO_AUDIO
 
         conditions {
-            ProfileConditionValue.AUDIO_CHANNELS lowerThanOrEquals if (downMixAudio) 2 else 8
+            ProfileConditionValue.AUDIO_CHANNELS lowerThanOrEquals
+                when {
+                    spdifArcSurroundAudio -> 6
+                    downMixAudio -> 2
+                    else -> 8
+                }
         }
     }
 

diff --git a/app/src/main/proto/WholphinDataStore.proto b/app/src/main/proto/WholphinDataStore.proto
@@ -57,6 +57,7 @@ message PlaybackOverrides{
   bool direct_play_dolby_vision_e_l = 6;
   bool decode_av1 = 7;
   AssPlaybackMode ass_playback_mode = 8;
+  bool spdif_arc_surround_audio = 9;
 }
 
 message PlaybackPreferences {

diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
@@ -788,4 +788,7 @@
         <item></item><!-- Intentionally blank -->
         <item></item><!-- Intentionally blank -->
     </array>
+    <string name="spdif_arc_surround_audio">SPDIF/ARC Surround Audio</string>
+    <string name="spdif_arc_surround_audio_summary_on">Force all audio to AC3 5.1 for SPDIF/ARC output</string>
+    <string name="spdif_arc_surround_audio_summary_off">Use default audio settings</string>
 </resources>