I did change from ISP, using my own ASUS router. Turning on / off DNS rebinding or entering DNS 8.8.8.8 and 8.8.4.4 on LAN settings didn’t help.
This seemed to do the trick though: Server settings are unavailable, can't access server via LAN (only plex.tv)
I did notice though that a lot of movies and series that had status watched are marked as unwatched again. I hope I don’t have to redo all of that again. It’s a shame there still is not a good solution yet to integrate with Trakt to restore watched status (as was previously possible with the plugins).
