Plexamp 4.50.x beta AAC LC playback issues Linux

Plex Labs
1

Hi team,

Unfortunately for some reason all of the new 4.50.x beta versions seem unable to playback any AAC LC files on Linux (using the AppImage)

Checking the logs, all the metadata is loaded from the server (latest non-beta version as of 2026-09-15) however the server receives back State “error”

The Plexamp player doesn’t crash, it just loads the next file until no more files or one that it’s able to play back.

Looking at the logs, it seems that it wrongly tries to use Opus to playback the file.

and because the files are .m4a with General format MPEG-4 and Audio Format AAC LC it somehow can’t play it (Taken from MediaInfo).

Previously something like this also happened with the older Plexamp when the General format was DASH, it wouldn’t play, however ffmpeg’ing the file to m4a solved the problem back then.

Steps to reproduce:

  • Download an audio stream from Youtube using yt-dlp -f 140 (which is the m4a audio only m4a_dash stream)
  • Then convert this m4a (with General format DASH) to m4a using ffmpeg -c for copy
  • Now set the metadata for the file and add to Plex
  • Then try to play it on Plexamp 4.50.x AppImage on Linux

If you need more info, let me know.

2

Use the flatpak

3

I’m using CachyOS (latest) with KDE without flatpak, what makes the flatpak version better / makes you sure it doesn’t fail there?

maybe i can figure out how to solve the AppImage problem that way.

4

try it and see

5

Appimage uses whatever libraries versions that are bundled in, It can be brittle to subtle architecture differences.
Flatpak pins a runtime, but the actual libraries they can get linked a little more freely.

This is especially an issue with something like ffmpeg that has a ton a compile options and can bundle codecs that you can’t ship as a commercial entity, but a OSS distribution can (flatpak).

6

Ignore what I said about the flatpak, that was wrong. The BASS decoder plugins aren’t loading at all on Linux in 4.50.x, and Opus is the only one that’s compiled in rather than loaded from a file, so it ends up the last one standing and gets handed everything, including your AAC. Same root cause as the FLAC report that came in today, it affects the flatpak and the deb as well as the AppImage, and the fix is in the next beta.

7

Hmm: correction, this isn’t a general problem, multiple testers have said it works fine, so I’m not sure what’s up with your system. Check the next beta, post logs if still having issues.