HI,
After the internet dropped out a couple of days ago Plex server now keeps disconnecting from DS 920+ running DSM 7.2.2.72806. NAS is on a static ip. I’ve got 2 x NVIDIA Shields running Plex player apps, when it disconnects from NAS it appears to be reconnecting to either NVIDIA Shield’s ip address, trying to use that as the server. I’ve rebooted, router, nas and stopped, re-run plex. It’ll show NAS as server for an amount of time and then go to one of those two options, sometimes going back to the nas.
Up until internet had dropped out it been working without any issues.
Uninstalled Plex on both nvidia shields, re installed above worked for awhile lost connection again.
Try rebooting your modem/router and everything connected to it, including any wireless devices. That should clear any DNS cache corruption which may be causing your issue.
Open Plex/Web using http://NAS-IP-ADDRESS:32400 and go to Plex Settings > Server > General and make sure your server is claimed.