To add to this, have installed WinTV 8.5 and 10 and it can see the tuner also, and operate as normal. Have since uninstalled wintv, devices and reinstalled drivers with no luck.
Still just get this…
Supported DVR Tuners and Antennas | Plex Support - Hauppauge Quad is on the list
Have updated plex to 1.21.4.4054 so last two versions have the issue, and
Windows Details are;
(only patch applied since the upgrade plex upgrade is the flash player removal)
Edition Windows 10 Pro
Version 20H2
OS build 19042.804
Experience Windows Feature Experience Pack 120.2212.551.0
Any suggestions?