A couple of things off the top of my head while I read your logs.
- Hello sorry it took so long. I saw chromcast and thought “no sir.”
- After install on the M1 check that Settings → Transcoder has HW selected. I think it’s off by default which is groovy.
- You’ve got a Plex Pass. So you can try out the amazing new Plex Media Server 1.29.2.6273 - New Transcoder Preview
- Chromecast lets hope it’s not that.