SOLVED: Remuxing?

[Alliyance]

Its remuxing, not transcoding.

Code:

-codec:v:0 copy .... -codec:a:0 copy

Your client doesn't support the codec/container combination.

I have the same issue with certain client on Chromecast, weird cause usually it's direct play. So it has nothing to do the Jellyfin custom ffmpeg? Someone stated that the server is using a vaninlla ffmepg instead of the custom jellyfin one.