New Tuner box on its way :-)
@Clare Newsome, just received confirmation that Fabrice is despatching a new tuner box for my Viera Z1 TV. Hopefully this will resolve my problems. I did independantly test the TV panel with source and that was much better behaved.
Many thanks to your Clare and Fabrice for making this happen. Touch wood that the new one will see the last of these gremlins!
Our problems on these forums are as nothing to those affected by the recent Japanese earthquake/tsunami - our thoughts and wishes should go out to the people of Japan and employees of Panasonic affected by this devastating tragedy.