Some lower end recievers, such as Onkyo, don't support HDCP, a copyright protection method. Basically, the source is sending an HDCP signal to the reciever, but the reciever, on routing, is not sending it back out. The television sees this, labels it copy protected and won't play. Sometimes, this will affect video, but almost all cases involve loss of audio. To fix: HDMI from source direct to TV, optical cable from source to reciever. You will lose video switchin capabilities, and the only fix that involves keeping those capabilities is buying a new reciever.
I have a Sharp LCD flat panel HDTV, Onkyo TX-SR605 receiver, Tivo Series 3, Playstation 3. I have HDMI cables from TV to receiver. I have no external speakers. I can't get the audio to work from the TV when I go through the receiver. Picture comes through fine. When I take the receiver out of the loop (Tivo and PS3 directly to TV via HDMI), everything works fine. I have tried all of the settings that make sense on the TV and receiver to get the TV audio to work. Anyone know what the deal is? Will the receiver only work with external speakers (which seems ridiculous)? Thanks.