I've had a Panasonoc TX28DT4C, the one with the built-in Freeview receiver, for a few months, and I'm very pleased with it. But when I'm tuned to AV1 or AV2 I can't get rid of the input/channel indicator at the top left-hand corner of the screen. It wasn't there at first, and I haven't changed any settings. Can it be removed? It also doesn't show on DVB channels, but does on Nicam.