Music playback sometimes stalls between tracks in Android Mobile app on cellular

[benmoses 4]

Running version 3.5.49

Library is a mix of flac and mp3 files.

When remote (cellular) bandwidth cap is set to 1Mbps I encounter this seemingly random stall cleanly, between tracks when playing a playlist of mixed mp3 and flac filetypes.  I noticed that most of the time currently playing flac file would be transcoded to AAC due to this limit.  This behavior is good and expected.  However it seems like if the next track after the currently playing, transcoded AAC file was an mp3 file, that's when the playback would stall between tracks.  The next song, the mp3 file, would not begin playing after the AAC track finished.

If I raised the remote (cellular) cap to 1.5 Mbps, no transcoding occurs and I get no playback stalling at all.  I can play a playlist for hours, no problem.  (However I chew through my cel plan pretty fast) <-- not good.  I think this means that flac and mp3's are coexisting just fine.

In a third scenario, I lowered the remote (cellular) cap to 256kbps, thought being "OK let's transcode everything", but to no avail I'm encountering the stalling again and I think it's for the same reason.  I think after an AAC transcoded track is played and an mp3 is next, the playback stalls.  (Reason being, even at 256kbps, the mp3 files still don't need to be transcoded.)

Is there a known issue with playback of mixed types here?  Can one force Emby server to transcode to mp3 instead of AAC?  I think I already know that there's no setting to force Emby to transcode in general, correct?

I'll post my log file here.  I used the anonymize button.

 

Thank you!

Ben

embyserver (1).txt

[Luke 42974]

Hi, I think we need to look at improving resiliency to network disruptions. I think it has more to do with that than transcoding vs not transcoding.

[benmoses 4]

I feel like it has to do with anytime there's a transition from HLS/AAC --> MP3 playback. (<-- or something related to contiguous but dissimilar file playback).

If I may, here's a snippet from AI helping me troubleshoot this problem from a while back.  I let AI ingest a portion of a log file.  This is what led me to try adjusting the remote (cellular) cap, which did work to keep the problem from happening.  I was using Emby Android 3.5.36 at this time (about 4 months ago or so).

Would the full debug and ffmpeg logs help?

 

The server did its job and handed off the next track correctly. The failure is on the client side — the Emby for Android app (v3.5.36) failed to start playing the new HLS stream and aborted right away.

Why This Happens (Especially Remotely)

• HLS Transcoding Handover Issues: Common on Android when skipping tracks in playlists remotely. The app's media player (ExoPlayer) sometimes chokes on starting the next transcoded segment, especially with FLAC sources or bitrate mismatches.
• Remote + Low Bitrate Cap: Your setup forces transcoding (good for bandwidth, but fragile for seamless playlist playback).
• App Version: 3.5.36 is fairly recent, but similar issues have been reported with FLAC/remote skips.

Quick Things to Try

• Raise the bitrate limit on the Android app (under Playback → Quality or Video Quality settings) to allow Direct Play/Stream for more files. Test if it reduces transcoding.
• Force lower quality or test with an all-MP3 playlist to see if FLAC sources are the trigger.
• Don't skip manually — let it play through naturally and see if auto-advance fails the same way.
• Local network test: Play the same playlist on Wi-Fi (same LAN). If it works, confirms remote/transcoding sensitivity.
• Update/reinstall: Ensure server is latest; try clearing app cache or reinstalling the Android app.

Next Steps for Logs

• Enable full debug on both server and Android app, reproduce, and grab:

  The matching ffmpeg transcode log for the ABBA track (should show what happened during that brief attempt).

  Android app debug log (via the app's "Send log" feature) — this will likely show ExoPlayer errors.

Edited 47 minutes ago by benmoses