I have a KDL-40W5810 which has just started losing the Freeview digital TV channels when turned off. The TV has been working fine for 4 years remembering the digital channels when turned off. If I put the TV in standby mode (with red light), then it appears to keep them. 

Also, the EPG guide is completely blank as well (when set to all) even after the digital TV is re-tuned. I have to go into the Favourites list to see any information in the guide.

Has anyone seen this problem before? I suspect it is some sort of battery gone flat or perhaps a ram chip.