I have a Panasonic Viera TX-32LZD81 TV which won't pick up some Freeview channels such as Drama (20), 5USA (21) or Horror (70). Retuning doesn't make any difference and I have a smaller non-Panasonic TV which does pick them up so I don't think it can be related to the local transmitter. Both TVs use internal aeriels. Any ideas on how to fix this (not - subscribe to a cable service!)?