SOLVED: Roku app mysteriously skipping to next episode

[duckrental]

When I try to watch certain TV episodes, at a certain point (about 1m30s in, in the cases I've seen), it skips ahead to the next episode. I am experiencing this issue on the Roku app only (on multiple devices, with app version 2.0.1; the issue also occurred with 2.0.0, but I do not recall experiencing it prior to that). The issue does not occur with the Windows client (version 1.9.1). The server is version 10.8.10, installed on Ubuntu through the official repositories.


Relevant section of the logs: https://pastebin.com/BdWsNFq2

MediaInfo of an affected file: https://pastebin.com/EvP9NFbP

The skip seems to happen at about where the subtitles start, but the issue also occurs when the sub track is turned off, so that may be a coincidence. Just in case, I extracted the SRT and took a look, but there doesn't seem to be anything wrong with it.

The first few lines of the sub track, just in case: https://pastebin.com/4uWVP1Z4

[1hitsong]

Do you have the custom subtitle setting enabled?

[duckrental]

Do you have the custom subtitle setting enabled?

I do not

[duckrental]

An update: I've tested a couple episodes from other series with SRT subs, and they do not experience this issue (or if they do, I didn't wait long enough for it to arise - I was only checking whether it was the start of the sub track that caused the issue)

[duckrental]

A further update: I have updated the server to 10.8.13; the problem persists. I have also tried enabling custom subtitles in the Roku client, which does not fix the problem; however, with custom subtitles enabled, the first subtitle line does show up right before the episode skips.

Logs: https://pastebin.com/AxKqvNsn
(The playback starting at 15:05 is with custom subtitles off, starting at 15:06 is with them on)

[TheDreadPirate]

FWIW, since everything is Direct Playing, the behavior you are describing is 100% a client side issue OR some issue with the file. The jellyfin server is just sending the file.

You can try using ffmpeg to check your files for errors.

Code:

/usr/lib/jellyfin-ffmpeg/ffmpeg -v error -i "/media/hdd/Anime/Tenchi Universe/[R2J-DarkDream] Tenchi Universe S01E06.mkv" -f null - 2>/tmp/error.log

[duckrental]

FWIW, since everything is Direct Playing, the behavior you are describing is 100% a client side issue OR some issue with the file.  The jellyfin server is just sending the file.

You can try using ffmpeg to check your files for errors.

Code:

/usr/lib/jellyfin-ffmpeg/ffmpeg -v error -i "/media/hdd/Anime/Tenchi Universe/[R2J-DarkDream] Tenchi Universe S01E06.mkv" -f null - 2>/tmp/error.log

Okay, tried this - the file it produces is empty, so I assume that means no errors in the mkv.

EDIT - Accidentally marked the wrong post as the solution - it's the next one

[TheDreadPirate]

The other possibility is that the MKVs were not authored properly.  I've seen issues with stuttering due to some issue with frame timestamps or something like that.  I don't fully understand the low level details.

We can repackage all the streams in your MKV without having to re-encode.

Code:

/usr/lib/jellyfin-ffmpeg/ffmpeg +genpts -i "/media/hdd/Anime/Tenchi Universe/[R2J-DarkDream] Tenchi Universe S01E06.mkv" -map 0:v -map 0:a -map 0:s -map_chapters 0 -c:v copy -c:a copy -c:s copy outputFile.mkv

Replace outputFile.mkv with whatever filename you want (don't overwrite the original).

[duckrental]

The other possibility is that the MKVs were not authored properly.  I've seen issues with stuttering due to some issue with frame timestamps or something like that.  I don't fully understand the low level details.

We can repackage all the streams in your MKV without having to re-encode.

Code:

/usr/lib/jellyfin-ffmpeg/ffmpeg +genpts -i "/media/hdd/Anime/Tenchi Universe/[R2J-DarkDream] Tenchi Universe S01E06.mkv" -map 0:v -map 0:a -map 0:s -map_chapters 0 -c:v copy -c:a copy -c:s copy outputFile.mkv

Replace outputFile.mkv with whatever filename you want (don't overwrite the original).

This seems to have fixed it, though ffmpeg didn't like +genpts so I replaced it with -fflags genpts.