Out of sync subtitles on transcoded content

[Narky]

Hi everyone,

I've been having issues with subtitles beeing out of sync, I have tested with several browsers (firefox, Opera, Brave), on the beggining of the stream the subtitles are ok, but if I jump ahead they get out of sync.

I have also tested on the android APP and AndroidTV APP, on these I have no issue, but realized there is a difference to the browser tests, on android there is no transcoding happening, so the issue apparently only happens on transcoded content.

I also saw a strange behaiour on the browser, when I'm playing a movie and click on settings, the subtitles deviation is constantly showing diferent values, I see it going from 9 to 0  and back to 9, like one per second (9,8,7,6,5,4,3,2,1,0,9,8...).

Sometimes the out of sync is only about 1 second, sometimes a few more seconds, so it's like when i jump to a movie position it's a gamble if i'm gonna be on sync or uo to 9 seconds out of sync.

Anyone else having this issue?

Is there any option that will correct this?

I'm runnig the latest jellyfin version (10.9.6) under Ubuntu 22.


Best Regards,
Luis Fonseca

[TheDreadPirate]

Can you share your jellyfin server logs via pastebin? Are the subtitles embedded?

[Narky]

Hi,

This is happening both with embedded and non embedded subtitles.

I've gathered Jellyfin and transcoding logs from a new test, you can check them here:

https://pastebin.com/R5x7FrPb
https://pastebin.com/vwngN4BF
https://pastebin.com/1YiRQGE2

I also realised that on the android where it's working fine, I also see that weired behaviour of the subtitles deviation value constantly changing, so this could be a diferent issue.

Thanks for the help.

Best Regards,
Luis Fonseca

[TheDreadPirate]

Did these subtitles come with the video?

[Narky]

I'm using subtitles downloaded from opensubtitles plugin and this is happening in pretty much every moovie I test, I believe this started happening during the 10.9 release, althought it also was the same time I migrated jellyfin to a new server (more powerfull) with the same OS.

Meanwhile I've done more tests and realized this is happening 99% on x265 media, x264 is working fine.

Any clue what could be causing this?

[TheDreadPirate]

Go ahead and submit a github issue. Include both your jellyfin and ffmpeg logs in appropriate boxes.

https://github.com/jellyfin/jellyfin/issues

[Narky]

Issue #12164 opened.

Thank you.