Best environment and settings for Jellyfin Player on old i7 CPU (HD 4600))

[TheDreadPirate]

That is a Coffee Lake CPU, of all the codecs listed for decoding in Jellyfin it supports all of them except AV1. Same on the encoding side. Low power encoding for H264 is supported, but not HEVC low power encoding. Low power encoding is OPTIONAL for Coffee Lake.

Tone mapping on the server is supported. It does require that you install Intel's OpenCL package, if you have not done so already.

https://en.wikipedia.org/wiki/Intel_Quic...d_encoding
https://jellyfin.org/docs/general/admini...nux-setups
https://jellyfin.org/docs/general/admini...r-encoding

Without being on your client system, it is hard to say what is going on. The ffmpeg log you shared is downmixing the audio from 7.1 to 5.1 while sending the 4K video unmodified.

Do you have issues across the board with 4K content? Or just this particular movie? If it is just this particular movie, the problem could be a malformed container.