I now feel very guilty about taking up your time, but I had no idea that the TBS drivers were incorporated into the "official" version of LibreELEC 8.2 The backend reports the chipset presumably, which threw me as I was expecting to see TBS6281. I have got things working although some of the TV channels, especially HD, freeze after a few seconds. This is a problem I had some time ago but it seemed to fix itself. However, this is not the problem I started with - that is fixed, thanks to your help.
I am most grateful and hope you will continue your excellent work on this software. Incidentally, this version of Kodi resolves an issue I have bemoaned for quite a while - the limited visible tags for music files, which is a pain for classical music. The new menu item "Roles" fixes this and I can now search by composer - I'm very happy about that!
Many thanks and best regards.