This sounds to be similar to a problem I had.when switching out of standby while a recording was in progress, I did not get a picture, just a blank screen. The PVR was however starting up, but the HDMI negotiation with the TV (Sony Bravia) was failing to establish contact. This can also cause ‘green screen’ problems on initial switch on. I never did fix it, despite trying all the suggestions on here and elsewhere, until I bought a new TV (Panasonic) and the problem went away.