Netflix can get me 4K content from the internet, through my ethernet, to my device. Plex can get me 4K content from my internal server, through my ethernet, to several of my devices.
Certain Plex client apps choke on any quality coming from the same Plex server over the same ethernet.
I can only assume a residential internet connection, which typically packet filters and shapes for uploading content? It's only a guess though, you might have much better options for residential ISP than I do.
Plex can get me 4K content from my internal server, through my ethernet, to several of my devices.
Across the internet as well or when you're on your local network? My experience has been (and like with all things YMMV) infinitely better watching at home than connecting to my VPN and trying to tunnel back, but I fully expected that because the local ISP places a pretty well enforced limit on uploads from residential lines.
Comparatively though, I don't think either of our connections for streaming content from our respective home media servers holds a candle to the infrastructure of Netflix, which is why my expectations are rather measured regarding the capabilities of Plex.
That said, I love it for what it is.
I'm measuring Plex on my LAN against Plex on my LAN. Some of my clients accept 4K streams with no problems. Other clients buffer an unwatchable amount even on 480p from the same server.
My purpose of bringing up Netflix was only to show that the client devices that are choking on 480p from Plex are capable of handling 4K streams.
Sampling all the way down to 480p is definitely odd behavior on a LAN--can't say I've run into that. Have you had much help from the usual spots? I'd be curious to help troubleshoot this sometime, sounds like an interesting nut to try cracking, or is it something inherent to the clients with the way they're decoding?