Plex doesn't work on Samsung QLED QE55Q7CAM



Hey forum, I bought a new samsung Qled QE55Q7CAM and installed Plex.
The application connected to the Plex MS with the Account but nommater which title I chose, I get a timeout and the Info "PLAYER_ERROR_CONNECTION_FAILED"
I tried via LAN and Wifi and have the same outcome.
Any Idea?