Limit ffmpeg CPU usage (no Hardware decoding/encoding)

[TheDreadPirate]

Making changes to the encoder is no longer supported starting with 10.9. Primarily due to security issues in ffmpeg that would not be fixed if custom ffmpeg binaries were allow.

The CPU usage you are seeing is from the AUDIO being transcoded. This will ALWAYS happen on the CPU. What you can do is enable transcode throttling IN JELLYFIN.

Dashboard > Playback > Transcoding. Scroll down to the bottom and check "Throttle Transcodes". That should pause ffmpeg after it gets 3 minutes ahead of playback (by default).