I am having a issue with my new Samsung UA55D7000 and Freeview HD.

I have HD tuned perfectly and twice now it basically just drops the digital channels and reverts to analog channels.

Has anyone had something similar? or can tell me what it could be?

I do have a booster on the antenna to increase the signal stregth, and the reception is crystal clear... 

When I tune the tv I make sure I select Digital only, but how can I lock the in...?