learning all the time...
This wikipedia article...
http://en.wikipedia.org/wiki/List_of_digital_terrestrial_television_channels_(UK)
Shows Channel 11 & 12 are Multiplex Com 5 and the table at the top explains Also Known as ARQ B unavailable on Freeview Lite.
And thare are many TV transmitters in the country but only 81 of them carry ALL Freeview channels - the remaining 1036 channels are freeview light (lite).
i.e. the Channels that are giving you grief Pick TV and Dave are not universally available throughout the country - so Stop bleating on about it - come to terms with your situation - and get over it and give up trying.
And why anybody should become agitated about Pick TV God only knows.
You are suffering weak-signal-syndrome.
Good luck...
Peccavi
May 2013