MKV Remuxing Issue

[ianjbattaglia]

Hey all!

Finally got around to setting up a Jellyfin server on my Synology DS418 NAS. I'm running Jellyfin 10.9.7. I have a number of MKV files, which playback fine via remuxing on the web browser, but when I try playback via my Hisense TV (running Jellyfin for Android TV 0.17.4), there's a good bit of buffering which leads to slow playback; I usually have to wait to let it buffer and playback then. 

It's totally fine when I access it via the browser or my Android phone, it's only on the TV I run into this issue. I don't have the option of hardware accelerated transcoding on this Synology model; is there anything else I could try to improve playback besides just transcoding the files myself before I add them to my server?

[Fate]

Can you share your jellyfin logs via pastebin? You can access the logs in the Jellyfin UI. Dashboard > Logs (in the left side near the bottom). There should be a log that begins with "log". Open that and copy and paste the entire thing into pastebin.

If there are any ffmpeg logs, share one of those too.

[ianjbattaglia]

Hmm, looking at the logs, it seems it's trying to transcode for playback on Android TV: all the logs when I was watching start "FFMPEG.Transcode."

Here's the link to the other log (pastebin deemed this "potentially offensive," so it's on PrivateBin): https://privatebin.net/?a86efe7e2100cfd9...SxpqWh1ZDJ

If it is trying to transcode rather than remux, is there a way to change that setting?

[TheDreadPirate]

It is transcoding because it needs to. My guess would be the subtitles need to be burned in. The problem is that you are not setup for hardware acceleration. The spec sheet says the Realtek RTD1296 has a media engine on it and I found this Synocommunity page that seems to indicate that there are builds of jellyfin-ffmpeg that support the RTD1296 CPU.

I don't know which hardware acceleration type you would need to select for that. Either VAAPI or V4L2.

[ianjbattaglia]

So potentially I should try VAAPI and V4L2 and see if that leads to better performance, or just transcode them on my main computer manually? If I want to try hardware acceleration, is there anything else I need to do?

[TheDreadPirate]

It's questionable whether hardware acceleration would work. But worth attempting.

Otherwise you would need to convert your media into a more compatible format. Tdarr can help automate that process.