Plex no longer sees my Hauppauge WinTV-quadHD tuner, "Add Device" scans forever

For the problem with Hauppauge DVRs where the Plex Tuner Service process was shutting down soon after launch, there has been a further fix that has just got release in 1.21.4.4054-bab510e86

See

  • (DVR) Plex Tuner Service would sometimes shut down while Plex Media Server was still running (#12223).