[Help] Jellyfin outputs stereo instead of 5.1 on Zidoo Z9S

[obi]

Hello,
I am a new Jellyfin user.
I have installed the Jellyfin server (10.10.3) in a Docker container on my Unraid NAS.
I’m encountering an issue with the Jellyfin client (Android TV 0.18.3) on my Zidoo Z9S media player.
This player is connected to an audio amplifier that handles sound decoding.
When I play a movie via Jellyfin, the player only outputs stereo sound, even though the audio tracks of my MKV files are in 5.1 (with various codecs like DTS, Dolby AC3, TrueHD, DTS-HD MA, etc.).
However, when I use the Zidoo's native app (HomeTheatre 4), there is no problem.
The 5.1 sound is correctly sent to my amplifier.
I have checked all the Jellyfin settings on both the client and the server, but I can’t figure out where the issue is coming from.
Could you please help me?

Thanks

[TheDreadPirate]

Do you have the audio output setting configured to "Downmix to stereo"?

[obi]

No, I did check that, and it's "DIRECT".

[theguymadmax]

Play some files and post the server and any FFmpeg logs.

[obi]

Here is a FFmpeg log:

Code:

{"Protocol":0,"Id":"78581c97515558a5a300fa8c21d61c87","Path":"/media/Films 3D/Dragon 2 3D.mkv","EncoderPath":null,"EncoderProtocol":null,"Type":0,"Container":"mkv","Size":13528042633,"Name":"Dragon 2 3D","IsRemote":false,"ETag":"1e70e085a33453b92008206183811ef8","RunTimeTicks":61151160000,"ReadAtNativeFramerate":false,"IgnoreDts":false,"IgnoreIndex":false,"GenPtsInput":false,"SupportsTranscoding":true,"SupportsDirectStream":true,"SupportsDirectPlay":true,"IsInfiniteStream":false,"UseMostCompatibleTranscodingProfile":false,"RequiresOpening":false,"OpenToken":null,"RequiresClosing":false,"LiveStreamId":null,"BufferMs":null,"RequiresLooping":false,"SupportsProbing":true,"VideoType":0,"IsoType":null,"Video3DFormat":null,"MediaStreams":[{"Codec":"dts","CodecTag":null,"Language":"fre","ColorRange":null,"ColorSpace":null,"ColorTransfer":null,"ColorPrimaries":null,"DvVersionMajor":null,"DvVersionMinor":null,"DvProfile":null,"DvLevel":null,"RpuPresentFlag":null,"ElPresentFlag":null,"BlPresentFlag":null,"DvBlSignalCompatibilityId":null,"Rotation":null,"Comment":null,"TimeBase":"1/1000","CodecTimeBase":null,"Title":null,"VideoRange":0,"VideoRangeType":0,"VideoDoViTitle":null,"AudioSpatialFormat":0,"LocalizedUndefined":null,"LocalizedDefault":"Par d\u00E9faut","LocalizedForced":null,"LocalizedExternal":"Externe","LocalizedHearingImpaired":null,"DisplayTitle":"Fre - DTS - 5.1 - Par d\u00E9faut","NalLengthSize":null,"IsInterlaced":false,"IsAVC":false,"ChannelLayout":"5.1","BitRate":768000,"BitDepth":null,"RefFrames":null,"PacketLength":null,"Channels":6,"SampleRate":48000,"IsDefault":true,"IsForced":true,"IsHearingImpaired":false,"Height":null,"Width":null,"AverageFrameRate":null,"RealFrameRate":null,"ReferenceFrameRate":null,"Profile":"DTS","Type":0,"AspectRatio":null,"Index":0,"Score":null,"IsExternal":false,"DeliveryMethod":null,"DeliveryUrl":null,"IsExternalUrl":null,"IsTextSubtitleStream":false,"SupportsExternalStream":false,"Path":null,"PixelFormat":null,"Level":0,"IsAnamorphic":null},{"Codec":"dts","CodecTag":null,"Language":"eng","ColorRange":null,"ColorSpace":null,"ColorTransfer":null,"ColorPrimaries":null,"DvVersionMajor":null,"DvVersionMinor":null,"DvProfile":null,"DvLevel":null,"RpuPresentFlag":null,"ElPresentFlag":null,"BlPresentFlag":null,"DvBlSignalCompatibilityId":null,"Rotation":null,"Comment":null,"TimeBase":"1/1000","CodecTimeBase":null,"Title":null,"VideoRange":0,"VideoRangeType":0,"VideoDoViTitle":null,"AudioSpatialFormat":0,"LocalizedUndefined":null,"LocalizedDefault":"Par d\u00E9faut","LocalizedForced":null,"LocalizedExternal":"Externe","LocalizedHearingImpaired":null,"DisplayTitle":"English - DTS - 5.1","NalLengthSize":null,"IsInterlaced":false,"IsAVC":false,"ChannelLayout":"5.1","BitRate":1536000,"BitDepth":null,"RefFrames":null,"PacketLength":null,"Channels":6,"SampleRate":48000,"IsDefault":false,"IsForced":false,"IsHearingImpaired":false,"Height":null,"Width":null,"AverageFrameRate":null,"RealFrameRate":null,"ReferenceFrameRate":null,"Profile":"DTS","Type":0,"AspectRatio":null,"Index":1,"Score":null,"IsExternal":false,"DeliveryMethod":null,"DeliveryUrl":null,"IsExternalUrl":null,"IsTextSubtitleStream":false,"SupportsExternalStream":false,"Path":null,"PixelFormat":null,"Level":0,"IsAnamorphic":null},{"Codec":"h264","CodecTag":null,"Language":null,"ColorRange":null,"ColorSpace":"bt709","ColorTransfer":"bt709","ColorPrimaries":"bt709","DvVersionMajor":null,"DvVersionMinor":null,"DvProfile":null,"DvLevel":null,"RpuPresentFlag":null,"ElPresentFlag":null,"BlPresentFlag":null,"DvBlSignalCompatibilityId":null,"Rotation":null,"Comment":null,"TimeBase":"1/1000","CodecTimeBase":null,"Title":null,"VideoRange":1,"VideoRangeType":1,"VideoDoViTitle":null,"AudioSpatialFormat":0,"LocalizedUndefined":null,"LocalizedDefault":null,"LocalizedForced":null,"LocalizedExternal":null,"LocalizedHearingImpaired":null,"DisplayTitle":"1080p H264 SDR","NalLengthSize":"4","IsInterlaced":false,"IsAVC":true,"ChannelLayout":null,"BitRate":17697839,"BitDepth":8,"RefFrames":1,"PacketLength":null,"Channels":null,"SampleRate":null,"IsDefault":true,"IsForced":false,"IsHearingImpaired":false,"Height":1080,"Width":1920,"AverageFrameRate":23.976025,"RealFrameRate":23.976025,"ReferenceFrameRate":23.976025,"Profile":"High","Type":1,"AspectRatio":"16:9","Index":2,"Score":null,"IsExternal":false,"DeliveryMethod":null,"DeliveryUrl":null,"IsExternalUrl":null,"IsTextSubtitleStream":false,"SupportsExternalStream":false,"Path":null,"PixelFormat":"yuv420p","Level":41,"IsAnamorphic":false},{"Codec":"PGSSUB","CodecTag":null,"Language":"fre","ColorRange":null,"ColorSpace":null,"ColorTransfer":null,"ColorPrimaries":null,"DvVersionMajor":null,"DvVersionMinor":null,"DvProfile":null,"DvLevel":null,"RpuPresentFlag":null,"ElPresentFlag":null,"BlPresentFlag":null,"DvBlSignalCompatibilityId":null,"Rotation":null,"Comment":null,"TimeBase":"1/1000","CodecTimeBase":null,"Title":null,"VideoRange":0,"VideoRangeType":0,"VideoDoViTitle":null,"AudioSpatialFormat":0,"LocalizedUndefined":"Non d\u00E9fini","LocalizedDefault":"Par d\u00E9faut","LocalizedForced":"Forc\u00E9","LocalizedExternal":"Externe","LocalizedHearingImpaired":"Malentendants","DisplayTitle":"Fre - PGSSUB","NalLengthSize":null,"IsInterlaced":false,"IsAVC":false,"ChannelLayout":null,"BitRate":null,"BitDepth":null,"RefFrames":null,"PacketLength":null,"Channels":null,"SampleRate":null,"IsDefault":false,"IsForced":false,"IsHearingImpaired":false,"Height":1080,"Width":1920,"AverageFrameRate":null,"RealFrameRate":null,"ReferenceFrameRate":null,"Profile":null,"Type":2,"AspectRatio":null,"Index":3,"Score":null,"IsExternal":false,"DeliveryMethod":null,"DeliveryUrl":null,"IsExternalUrl":null,"IsTextSubtitleStream":false,"SupportsExternalStream":true,"Path":null,"PixelFormat":null,"Level":0,"IsAnamorphic":null}],"MediaAttachments":[],"Formats":[],"Bitrate":20001839,"FallbackMaxStreamingBitrate":null,"Timestamp":null,"RequiredHttpHeaders":{},"TranscodingUrl":null,"TranscodingSubProtocol":0,"TranscodingContainer":null,"AnalyzeDurationMs":null,"DefaultAudioStreamIndex":null,"DefaultSubtitleStreamIndex":null,"HasSegments":false}

/usr/lib/jellyfin-ffmpeg/ffmpeg -analyzeduration 200M -probesize 1G -fflags +genpts  -i file:"/media/Films 3D/Dragon 2 3D.mkv" -map_metadata -1 -map_chapters -1 -threads 0 -map 0:2 -map 0:0 -map -0:s -codec:v:0 copy -bsf:v h264_mp4toannexb -start_at_zero -codec:a:0 aac -ac 2 -ab 256000 -af "volume=2" -copyts -avoid_negative_ts disabled -max_muxing_queue_size 2048 -f hls -max_delay 5000000 -hls_time 6 -hls_segment_type mpegts -start_number 0 -hls_segment_filename "/config/cache/transcodes/db8577dc4ef0a032b876b14fcf87acc2%d.ts" -hls_playlist_type vod -hls_list_size 0 -y "/config/cache/transcodes/db8577dc4ef0a032b876b14fcf87acc2.m3u8"


ffmpeg version 7.0.2-Jellyfin Copyright (c) 2000-2024 the FFmpeg developers
  built with gcc 14.2.1 (GCC) 20240910
  configuration: --prefix=/usr/lib/jellyfin-ffmpeg --target-os=linux --extra-version=Jellyfin --disable-doc --disable-ffplay --disable-ptx-compression --disable-shared --disable-libxcb --disable-sdl2 --disable-xlib --enable-gpl --enable-version3 --enable-static --enable-gmp --enable-gnutls --enable-chromaprint --enable-libfontconfig --enable-libass --enable-libbluray --enable-libdrm --enable-libfreetype --enable-libfribidi --enable-libmp3lame --enable-libopus --enable-libopenmpt --enable-libtheora --enable-libvorbis --enable-libdav1d --enable-libsvtav1 --enable-libwebp --enable-libvpx --enable-libx264 --enable-libx265 --enable-libzvbi --enable-libzimg --enable-libshaderc --enable-libplacebo --enable-vulkan --enable-opencl --enable-vaapi --enable-amf --enable-libvpl --enable-ffnvcodec --enable-cuda --enable-cuda-llvm --enable-cuvid --enable-nvdec --enable-nvenc
  libavutil      59.  8.100 / 59.  8.100
  libavcodec    61.  3.100 / 61.  3.100
  libavformat    61.  1.100 / 61.  1.100
  libavdevice    61.  1.100 / 61.  1.100
  libavfilter    10.  1.100 / 10.  1.100
  libswscale      8.  1.100 /  8.  1.100
  libswresample  5.  1.100 /  5.  1.100
  libpostproc    58.  1.100 / 58.  1.100
Input #0, matroska,webm, from 'file:/media/Films 3D/Dragon 2 3D.mkv':
  Metadata:
    title          : Dragon2
    encoder        : libebml v1.3.0 + libmatroska v1.4.1
    creation_time  : 2014-10-29T10:30:53.000000Z
  Duration: 01:41:55.12, start: 0.000000, bitrate: 17697 kb/s
  Chapters:
    Chapter #0:0: start 0.000000, end 207.999000
      Metadata:
        title          : (01)00:00:00:000
    Chapter #0:1: start 207.999000, end 320.695000
      Metadata:
        title          : (02)00:03:27:999
    Chapter #0:2: start 320.695000, end 466.007000
      Metadata:
        title          : (03)00:05:20:695
    Chapter #0:3: start 466.007000, end 616.032000
      Metadata:
        title          : (04)00:07:46:007
    Chapter #0:4: start 616.032000, end 796.337000
      Metadata:
        title          : (05)00:10:16:032
    Chapter #0:5: start 796.337000, end 1019.059000
      Metadata:
        title          : (06)00:13:16:337
    Chapter #0:6: start 1019.059000, end 1201.700000
      Metadata:
        title          : (07)00:16:59:059
    Chapter #0:7: start 1201.700000, end 1423.255000
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    Chapter #0:8: start 1423.255000, end 1634.466000
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        title          : (09)00:23:43:255
    Chapter #0:9: start 1634.466000, end 1761.468000
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    Chapter #0:10: start 1761.468000, end 2021.936000
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    Chapter #0:12: start 2225.473000, end 2346.969000
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    Chapter #0:13: start 2346.969000, end 2459.165000
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        title          : (14)00:39:06:969
    Chapter #0:14: start 2459.165000, end 2703.992000
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        title          : (15)00:40:59:165
    Chapter #0:15: start 2703.992000, end 2836.625000
      Metadata:
        title          : (16)00:45:03:992
    Chapter #0:16: start 2836.625000, end 3111.525000
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    Chapter #0:17: start 3111.525000, end 3275.730000
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    Chapter #0:19: start 3375.997000, end 3633.171000
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    Chapter #0:20: start 3633.171000, end 3868.781000
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    Chapter #0:21: start 3868.781000, end 3994.949000
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    Chapter #0:22: start 3994.949000, end 4184.138000
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    Chapter #0:23: start 4184.138000, end 4441.854000
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    Chapter #0:24: start 4441.854000, end 4715.127000
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        title          : (25)01:14:01:854
    Chapter #0:25: start 4715.127000, end 4867.153000
      Metadata:
        title          : (26)01:18:35:127
    Chapter #0:26: start 4867.153000, end 4975.053000
      Metadata:
        title          : (27)01:21:07:153
    Chapter #0:27: start 4975.053000, end 5070.065000
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    Chapter #0:28: start 5070.065000, end 5284.654000
      Metadata:
        title          : (29)01:24:30:065
    Chapter #0:29: start 5284.654000, end 5463.499000
      Metadata:
        title          : (30)01:28:04:654
    Chapter #0:30: start 5463.499000, end 5541.994000
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    Chapter #0:31: start 5541.994000, end 6114.858000
      Metadata:
        title          : (32)01:32:21:994
    Chapter #0:32: start 6114.858000, end 6115.116000
      Metadata:
        title          : (33)01:41:54:858
  Stream #0:0(fre): Audio: dts (dca) (DTS), 48000 Hz, 5.1(side), fltp, 768 kb/s (default) (forced)
  Stream #0:1(eng): Audio: dts (dca) (DTS), 48000 Hz, 5.1(side), fltp, 1536 kb/s
  Stream #0:2: Video: h264 (High), yuv420p(tv, bt709, progressive), 1920x1080, SAR 1:1 DAR 16:9, 23.98 fps, 23.98 tbr, 1k tbn (default)
  Stream #0:3(fre): Subtitle: hdmv_pgs_subtitle (pgssub), 1920x1080
Stream mapping:
  Stream #0:2 -> #0:0 (copy)
  Stream #0:0 -> #0:1 (dts (dca) -> aac (native))
Press [q] to stop, [?] for help
Output #0, hls, to '/config/cache/transcodes/db8577dc4ef0a032b876b14fcf87acc2.m3u8':
  Metadata:
    encoder        : Lavf61.1.100
  Stream #0:0: Video: h264 (High), yuv420p(tv, bt709, progressive), 1920x1080 [SAR 1:1 DAR 16:9], q=2-31, 23.98 fps, 23.98 tbr, 90k tbn (default)
  Stream #0:1: Audio: aac (LC), 48000 Hz, stereo, fltp, 256 kb/s (default) (forced)
      Metadata:
        encoder        : Lavc61.3.100 aac
size=N/A time=00:00:00.00 bitrate=N/A speed=  0x   
size=N/A time=00:00:00.49 bitrate=N/A speed=0.491x   
size=N/A time=00:00:02.24 bitrate=N/A speed=1.49x   
size=N/A time=00:00:04.43 bitrate=N/A speed=2.22x   
[hls @ 0x556ab6eada00] Opening '/config/cache/transcodes/db8577dc4ef0a032b876b14fcf87acc20.ts' for writing
size=N/A time=00:00:06.25 bitrate=N/A speed= 2.5x   
size=N/A time=00:00:07.87 bitrate=N/A speed=2.62x   
size=N/A time=00:00:10.19 bitrate=N/A speed=2.91x   
[hls @ 0x556ab6eada00] Opening '/config/cache/transcodes/db8577dc4ef0a032b876b14fcf87acc21.ts' for writing
size=N/A time=00:00:12.28 bitrate=N/A speed=3.07x   
size=N/A time=00:00:13.48 bitrate=N/A speed=2.99x   
size=N/A time=00:00:15.65 bitrate=N/A speed=3.13x   
size=N/A time=00:00:18.07 bitrate=N/A speed=3.28x   
[hls @ 0x556ab6eada00] Opening '/config/cache/transcodes/db8577dc4ef0a032b876b14fcf87acc22.ts' for writing
size=N/A time=00:00:19.17 bitrate=N/A speed= 3.2x   
size=N/A time=00:00:21.50 bitrate=N/A speed=3.31x   
size=N/A time=00:00:23.89 bitrate=N/A speed=3.41x   
[hls @ 0x556ab6eada00] Opening '/config/cache/transcodes/db8577dc4ef0a032b876b14fcf87acc23.ts' for writing
size=N/A time=00:00:24.34 bitrate=N/A speed=3.24x   
size=N/A time=00:00:24.85 bitrate=N/A speed=3.11x   
size=N/A time=00:00:25.34 bitrate=N/A speed=2.98x   
size=N/A time=00:00:27.00 bitrate=N/A speed=  3x   
size=N/A time=00:00:29.26 bitrate=N/A speed=3.08x   
[hls @ 0x556ab6eada00] Opening '/config/cache/transcodes/db8577dc4ef0a032b876b14fcf87acc24.ts' for writing
size=N/A time=00:00:30.86 bitrate=N/A speed=3.09x   
size=N/A time=00:00:32.53 bitrate=N/A speed= 3.1x   
size=N/A time=00:00:35.05 bitrate=N/A speed=3.19x   
[hls @ 0x556ab6eada00] Opening '/config/cache/transcodes/db8577dc4ef0a032b876b14fcf87acc25.ts' for writing
size=N/A time=00:00:36.84 bitrate=N/A speed= 3.2x   
size=N/A time=00:00:38.86 bitrate=N/A speed=3.24x   
[hls @ 0x556ab6eada00] Opening '/config/cache/transcodes/db8577dc4ef0a032b876b14fcf87acc26.ts' for writing
size=N/A time=00:00:41.66 bitrate=N/A speed=3.33x   
size=N/A time=00:00:43.07 bitrate=N/A speed=3.31x   
size=N/A time=00:00:45.61 bitrate=N/A speed=3.38x   
[hls @ 0x556ab6eada00] Opening '/config/cache/transcodes/db8577dc4ef0a032b876b14fcf87acc27.ts' for writing
size=N/A time=00:00:47.68 bitrate=N/A speed= 3.4x   
size=N/A time=00:00:49.49 bitrate=N/A speed=3.41x   
size=N/A time=00:00:52.26 bitrate=N/A speed=3.48x   
[hls @ 0x556ab6eada00] Opening '/config/cache/transcodes/db8577dc4ef0a032b876b14fcf87acc28.ts' for writing
size=N/A time=00:00:54.05 bitrate=N/A speed=3.49x   
size=N/A time=00:00:56.36 bitrate=N/A speed=3.52x   
size=N/A time=00:00:58.96 bitrate=N/A speed=3.57x   
[hls @ 0x556ab6eada00] Opening '/config/cache/transcodes/db8577dc4ef0a032b876b14fcf87acc29.ts' for writing
size=N/A time=00:01:00.58 bitrate=N/A speed=3.56x   
size=N/A time=00:01:02.12 bitrate=N/A speed=3.55x   
size=N/A time=00:01:04.42 bitrate=N/A speed=3.58x   
[hls @ 0x556ab6eada00] Opening '/config/cache/transcodes/db8577dc4ef0a032b876b14fcf87acc210.ts' for writing
size=N/A time=00:01:06.49 bitrate=N/A speed=3.59x   
size=N/A time=00:01:07.49 bitrate=N/A speed=3.55x   
size=N/A time=00:01:09.54 bitrate=N/A speed=3.56x   
size=N/A time=00:01:12.17 bitrate=N/A speed=3.61x   
[hls @ 0x556ab6eada00] Opening '/config/cache/transcodes/db8577dc4ef0a032b876b14fcf87acc211.ts' for writing


[q] command received. Exiting.

[hls @ 0x556ab6eada00] Opening '/config/cache/transcodes/db8577dc4ef0a032b876b14fcf87acc212.ts' for writing
[out#0/hls @ 0x556ab6aafa00] video:146895KiB audio:2315KiB subtitle:0KiB other streams:0KiB global headers:0KiB muxing overhead: unknown
size=N/A time=00:01:14.02 bitrate=N/A speed= 3.6x   
[aac @ 0x556ab3db4380] Qavg: 6955.901

There is indeed somthing strange here :

Code:

Stream #0:0(fre): Audio: dts (dca) (DTS), 48000 Hz, 5.1(side), fltp, 768 kb/s (default) (forced)
  Stream #0:1(eng): Audio: dts (dca) (DTS), 48000 Hz, 5.1(side), fltp, 1536 kb/s
  Stream #0:2: Video: h264 (High), yuv420p(tv, bt709, progressive), 1920x1080, SAR 1:1 DAR 16:9, 23.98 fps, 23.98 tbr, 1k tbn (default)
  Stream #0:3(fre): Subtitle: hdmv_pgs_subtitle (pgssub), 1920x1080
Stream mapping:
  Stream #0:2 -> #0:0 (copy)
  Stream #0:0 -> #0:1 (dts (dca) -> aac (native))
Press [q] to stop, [?] for help
Output #0, hls, to '/config/cache/transcodes/db8577dc4ef0a032b876b14fcf87acc2.m3u8':
  Metadata:
    encoder        : Lavf61.1.100
  Stream #0:0: Video: h264 (High), yuv420p(tv, bt709, progressive), 1920x1080 [SAR 1:1 DAR 16:9], q=2-31, 23.98 fps, 23.98 tbr, 90k tbn (default)
  Stream #0:1: Audio: aac (LC), 48000 Hz, stereo, fltp, 256 kb/s (default) (forced)

Why does Jellyfin transcode the audio track to aac?
Is this the normal behavior of Jellyfin? My Unraid server has very limited hardware and is only used as a storage server for MKV files. It's not designed for transcoding (my Zidoo media player handles the video decoding, and my amplifier handles the audio).
However, when I stream, Jellyfin shows "Direct Play - The source file is fully compatible with this client, and the session is receiving the file without modifications."
I don't really understand what's going on here...

[theguymadmax]

I don't see why it would be transcoding and downmixing to stereo. Try clearing the data, deleting the app, and reinstalling it.

[obi]

Clearing the data of what ?
Thanks

[theguymadmax]

On the Android platform, go to Settings > Apps, then select Jellyfin, and you should be able to clear the app data.

   

[obi]

So, I did clear the app data, delete and reinstall it... But it still doesn't work.
Jellyfin always downconverts the audio to aac!

I even tried on another android box (Xiaomi Mi Box S), and it's the same thing : stereo instead of 5.1 tracks
Maybe it's a bad setting of the Jellyfin server but which ?!
I don't know.

If you have more ideas...
Thanks

[theguymadmax]

Try this:

1. Install Just Player. It's on the Google Play Store.
   
2. In the Jellyfin ATV client, go to Settings-> Playback-> Advanced Playback Preferences, and select Use External Player.
   
3. Play an item, and then choose Just Player as the external player.
   

When you use an external player, Jellyfin will attempt to play the file directly without transcoding.