SOLVED: Playback Error MKV

[Rubber9146]

As the title and the Description tells you I get these errors on playing my movie that is a mkv file.
The log in my /var/log/jellyfin/log_20231124.log tells me nothing about the issue, just authorization messages from my user there.

Because I only use it locally I try to figure out on how to just not use transcoding at all.

Jellyfin is installed on almalinux 9 LXC in my proxmox environment.

Can someone help out to further debug this?

[use7]

What's the error specficically?  The whole 'server isn't sending compatible format' one?  Do you have transcoding enabled (even if you don't want to long-term, but it could be either audio or video codec incompatibilities and could help with troubleshooting)?  If there's any type of transcoding going on there should be FFmpeg.Transcode-XYZ.log files generated, or are there none of these?  What client are you using (firefox/ jelly media player/ etc)? What are the codecs for the file(s) you're attempting to play?  (you can look at this through either ffprobe or by navigating to the file and selecting 'media info' from the kebab icon).  I know that .mkv containers require remuxing depending on your client so a different container may fit your needs better if you want no muxing to happen (though I don't know your scenario so take that may not be a relevant factoid for your use case).

[Rubber9146]

What's the error specficically?  The whole 'server isn't sending compatible format' one?  Do you have transcoding enabled (even if you don't want to long-term, but it could be either audio or video codec incompatibilities and could help with troubleshooting)?  If there's any type of transcoding going on there should be FFmpeg.Transcode-XYZ.log files generated, or are there none of these?  What client are you using (firefox/ jelly media player/ etc)? What are the codecs for the file(s) you're attempting to play?  (you can look at this through either ffprobe or by navigating to the file and selecting 'media info' from the kebab icon).  I know that .mkv containers require remuxing depending on your client so a different container may fit your needs better if you want no muxing to happen (though I don't know your scenario so take that may not be a relevant factoid for your use case).

the error message is in the description of this thread, but like the one you asked in the 2nd question.
There is no FFmpeg log (I already tried to disable transcoding by disabling the rights for transcoding for the specific user).

I figured something out: The video isn't playing on jellyfin App for iOS but on Swiftfin. The video isn't playing on Brave but on Microsoft Edge. With my good old plex installation, it is running on all browsers and on the native app from plex.

[TheDreadPirate]

Sounds like you don't have transcoding setup.

[Rubber9146]

What's the error specficically?  The whole 'server isn't sending compatible format' one?  Do you have transcoding enabled (even if you don't want to long-term, but it could be either audio or video codec incompatibilities and could help with troubleshooting)?  If there's any type of transcoding going on there should be FFmpeg.Transcode-XYZ.log files generated, or are there none of these?  What client are you using (firefox/ jelly media player/ etc)? What are the codecs for the file(s) you're attempting to play?  (you can look at this through either ffprobe or by navigating to the file and selecting 'media info' from the kebab icon).  I know that .mkv containers require remuxing depending on your client so a different container may fit your needs better if you want no muxing to happen (though I don't know your scenario so take that may not be a relevant factoid for your use case).

the error message is in the description of this thread, but like the one you asked in the 2nd question.
There is no FFmpeg log (I already tried to disable transcoding by disabling the rights for transcoding for the specific user).

I figured something out: The video isn't playing on jellyfin App for iOS but on Swiftfin. The video isn't playing on Brave but on Microsoft Edge. With my good old plex installation, it is running on all browsers and on the native app from plex.

My idea was (or at least hope) that I can turn off transcoding with these checkboxes turned off. If I turn them on again, I can play anything on the native app and brave.
So question will be, how can I stop it from transcoding?

[TheDreadPirate]

If you want to avoid transcoding because the server just can't, you would use Jellyfin Media Player on a desktop and one of the apps on whatever device you have. AFAIK, Swiftfin has a better underlying player than the Jellyfin Mobile app.

[use7]

I see you've marked Solved, just wanted to tack on that the transcoding/muxing only happens when it is necessary (either from codec/container compatability issues, which are documented in the chart that was linked in my anser, or because there are bitrate limits) in JF.  Probably the easiest way is installing a player with broad support (JMP as suggested by DreadPirate above) or by using containers/codecs widely supported (I think h264 in mp4 with aac audio is probably going to be most broadly applicable).  There's also the caveot that if you're attempting to watch something with a high bitrate through a weak connection (thinking raw bluray file through public wifi) you're probably going to need to transcode it down, so I usually recommend leaving transcoding enabled.  Though by matching formats you can reduce how often you need to transcode a file.

On a related note, you can set up versions so that you can transcode files externally (ffmpeg/handbrake/etc.) and request different resolutions/bitrates without on-the-fly transcoding (at the cost of disk space).