Today I decided it was time to update to Android 12. Now I deeply regret my decision. All TV functions (picture mode, sound output, channel selection etc) stopped working. Only apps work. I can't watch watch broadcast TV either. No Freeview, no Freesat. Any attempt to use these functions and all I get is either no response at all or a second or two of dark screen and back to Home. 

Has anyone seen this behaviour? I'm desperately trying to avoid resetting the TV and lose my configuration, end up in a worse place, or both. 

Thanks.