SOLVED: Playback speed causes stutter and jumps

[advarito]

Issue:
When trying to speed up ANY video on jellyfin, regardless of long movie or short video (20min or less), the video starts stuttering and/or jumping.
I try to describe as best as I can:
The video will, instead of play smoothly, start to jump the image a couple of frames, in regular intervals. Meaning, for example, every 0.5 seconds, have a jump to several frames ahead. This is very noticeable in smooth-moving scenes, like showing a panoramic of a city.
The bigger is the playback speed, the bigger are those jumps in frames.

I hope someone can help me fix this issue.

I will be more than happy to provide any other information necessary.

Client: Fire-TV 4k

Server: 
OS: Windows 10
CPU : Ryzen 5 5600X
GPU: GTX 1060 6gb
ram: 16gb
Jellyfin Version 10.8.10

[TheDreadPirate]

Is your server transcoding? Are you using your GPU to accelerate transcoding? What codec are you using for your videos?

Can you upload your jellyfin and ffmpeg logs to pastebin and share them here?

[advarito]

I do not know 100% sure if I am transcoding.

here are my settings for playback: (I did not change anything, so it should be as it came from install)
https://pasteboard.co/mCHLXpcFtoFa.png
playback settings

Seems like, for example in this series I am not transcoding, but still having the same issue, so I guess it is not transcoding related:
Dash board shows Direct Play: https://pasteboard.co/RtCuFchDbSmF.png

Jellyfin log: (on a different site because exceeds pastebins 500kb max)
https://paste.ee/p/05NXn

ffmpeg log: I have noticed that the file on the beginning nor the path, match the series/chapters I was watching, meaning that the issue might not be related no transcoding?
https://pastebin.com/9SPJvDGr

Thanks

[TheDreadPirate]

Your playbacks start as direct play, but switches to transcoding because the subtitle format isn't supported. It is probably burning in the subtitles. This also happens to me on my Chromecast with Google TV.

It looks like it is transcoding fast enough, even though it is all on the CPU. But you would probably have a smoother playback experience with NVENC on. In the playback settings at the top, change Hardware acceleration to NVENC.

Check these boxes

H264
HEVC
MPEG2
VC1
HEVC 10bit
Enable hardware encoding
Allow encoding in HEVC format

[advarito]

Did it, the result is the same, stutter and jumps.
I even tried without subtitles, selecting 'none' on the client (fireTV).
Issue persist.
Could it be that the fireTV is just not powerful enough? (I don't think so because it also happens with you Chromecast, but to discard possibilities)

EDIT: After the transcoding settings change, now the server nor the phone can play the videos:

Playback error

This client isn't compatible with the media

and the server isn't sending a compatible

media format

After reverting the changes by setting hardware Transcoding to 'None' it plays on the clients, but still the same problem

[TheDreadPirate]

For clarification, my Chromecast doesn't stutter. Just that it requires transcoding with some subtitles.

The FireTV SHOULD be powerful enough. Especially since it doesn't look like your video is 4K. This is definitely a client side problem and not a server problem.

Some old reddit posts suggested that clearing the Jellyfin app cache on the FireTV might help. Some people said reinstall the app on the FireTV worked for them.

[advarito]

W0W
Those old reddit posts were gold. I feel dumb for not trying that first, good old uninstall/reinstall, took 1 minute and fixed.

thank you very much!