Problems streaming 4k

[Snack]

Hi.

Plex Server got i7-6700 CPU @ 3.4 Ghz is conncetet to my Apple TV 4K via a Gigabit switch.

I tryed many diferent 4K files byt it always takes my CPU up to 100 % andt the client is responding that the server is to slow.

[Mkl]

Use SRT subtitles, not PGS or ASS