Relay is limiting the available bandwidth to 1mbps for users without Plex pass.
So what you are seeing is what would happen if Relay is being used.
Look at the server’s Dashboard during such a playback. If Relay is being used, the connection type will appear as “indirect”.
https://support.plex.tv/articles/200871837-status-and-dashboard/
If Relay is being used, it means that the client app is unable to reach your server directly.
This can be caused by several things. Among the most frequent are
- no publicly accessible IPv4 address on the server’s router. Typically caused by the ISP putting you behind a
Carrier-Grade NAT, to save on scarce IPv4 addresses - “double NAT” caused by using either more than 1 gateway device (i.e. “router”) or by running the server in a container or virtual machine with the network of that container being separated from the host machine’s network
- misconfiguration of the router on the server’s side. Usually either by disallowing UPnP, or by telling Plex that a manual port forwarding is used, but it was never created in the router’s settings.
In general: the longer the geographical distance between server and client, the more important the network packet roundtrip time is becoming. Particularly if the file must be transcoded. Because if that happens, it is transcoded in little chunks, which are transmitted each on its own, instead of one contiguous stream of data.
Packet roundtrip time is particularly long if wireless networking is involved or (worse) satellite links.
Have you ever tested to access your own server while being out of house?
