I came across this forum while setting up my Plex Server (on Umbrel) and watching my local media on a PS5. After a lot of digging and trial and error, I’ve got it working. I ran into an authentication issue which was easily solved then ran into the indirect server problem. The 1080p movie I wanted to watch wouldn’t load and would only buffer. I saw a few closed threads on this and wanted to share my experience to hopefully help anyone out there having the same issues. In short, it’s a port issue, and it was a pretty easy fix once I got my head around it.
I just watched The Northman (in 1080p) with no buffering or any other issues. Hope this helps! Happy to be here!