Having sent one tv back because of this problem, and having received a new one today, only to find it still has a problem, what can be done to fix this? I've used a set up disc and at the clamping test it gets all very confusing. the test says the black box in the centre of the screen should remain the same colour through out the test but the box is grey not black and it does change colour(i think???) anyway, in practice this means when i watch aliens, some scenes get smokey blacks instead of true blacks. its all a bunch of arse. can clamping problems be fixed in situ or must they go back to the factory? any advice, please???