OK cool, I just wondered if finally a Plex employee would take this seriously. But if you can help me, it would be cool too.
In fact, thanks to you I figured out that there is indeed something wrong with the streaming part. I keep getting the playback error related to excessive buffering, even when I only have sound stutter, so the video keeps playing.
My smart TV is connected directly to the router via LAN cable, so no WIFI. Keep in my mind, that I have no bandwidth problems since other apps like Netflix, Prime Video, Disney+ and YouTube work just fine.
So the problem must be with Plex, perhaps there is something wrong with my account? But that can’t be it, since I don’t have the problem on my laptop. I haven’t looked into adjusting playback quality, but full HD shouldn’t be a problem.