I have not bothered trying to connect my ATV4 Plex Beta client to my Plex Cloud server for some time. I gave up due to long buffer times, hangs and dropout and instead stream Plex Cloud to Shield TV.
I still use ATV4 Plex Beta client to stream from my local Plex Sever and it does work well with this.
Anyway, a few times lately I have tried again to stream ATV4 Plex Beta client from my Plex Cloud and the same old issues still occur… 8 to 20 second buffer when starting a movie, then several hangs during playback… i.e. useless
I think it’s been mentioned elsewhere, but setting Mr MC on my ATV4 to connect to Plex Cloud streams seamlessness. Instant playback and no hangs. Wish the official Plex client could do the same.