For the last few nights when i've been watching bbc1 i get a blue screen and a message saying no signal is being recieved. I then can't get bbc1,bbc2,itv,channel 4 and channel 5. Allthe other channels seem to be ok but the only way to rectify this is to turn it off at the mains and then re-boot it. The screen started freezing tonight before it went off which has never happened. Thing is i'm worried if it's a fault with the box, has anyone else had this? I think it is possibly still under 12 months old so surely sky will either fix or replace this? Any advice?