panasonic sky box

[jonnyboy]

hi all, i now have 2 of these boxes. one has the fault of no signal recieved and the other one breaks up to squares, seems to be worse with the more content in the picture, e.g a news report is ok to watch but put on say a music channel and it really breaks up and freezes. does any one have any ideas?? on both boxes the built in signal meter reads ok for both strength and quality. thanks in advance, Jon.