I just bought a TiVo Series 3 to go with my new Panasonic 58" plasma TV and new Panasonic Home Theater system. The TV has 2 HDMI inputs and a digital optical audio output. I have the home theater (DVD player) connected to the HDMI1 input, and the TiVo hooked up to the other HDMI input, and the optical audio output from the TV feeding the home theater system. Several times now, I have totally lost the audio feed on both live TV and on recorded shows on the TiVo. However, when this happens I can still hear the TiVo sound effects.

Trying to track down the source of the problem, I tried the following:

• Turning on the TV's speakers has no effect (still no audio)
• Turning the home theater system off and back on has no effect (still no audio)
• Changing channels, watching different recorded show, etc, has no effect
• Taking the optical digital audio out straight from the TiVo has no effect (no audio on this output, either, except TiVo sound effects)
• Plugging a different source into the same input on the home theater, I can hear it fine. Plugging the TV audio out back in (or the TiVo audio out) is still silent.
• It appears that audio is actually recorded on recorded shows, I just lose playback. On recorded shows where I can't hear audio, if I can restore audio later, I can hear audio on those shows.
• Resetting the TiVo restores audio
• Here is the wierd part: SOMETIMES, cycling the TV inputs through the alternate inputs (HDMI1, COMPOSITE1, etc) will restore audio on HDMI2

I was ready to blame the TiVo (still am , actually) except cycling the TV inputs solves the problem sometimes. I think the problem might be related to the Panasonic EZSync HDMI control signals. Panasonic apparently sends signals through the HDMI cable to tell other Panasonic equipment what to do (so when I turn off my TV, it turns off the Panasonic home theater; when I switch the TV to the DVD input, it switches the home theater to DVD mode as well, and vice versa, etc).

I don't think it is the TV per se, because the optical audio output from the TiVo is "muted" as well.
I don't think it is the CableCards, because the problem occurs during playback of recorded shows (and audio was apparently recorded, because later I can play it again and hear audio).
I don't think it is the home theater system, because I can hook other equipment to the optical audio input and hear them.

This seems to leave the Tivo, which is apperently either flaky on its own, or somehow interpreting / getting confused by the Panasonic's control signals. I am thinking about switching the TiVo to one of the Component Video inputs on the TV to see if this solves the problem, but the TV weighs 150lbs and is on the wall, with the inputs in the back.

I am wondering if anyone else has had similar problems with Panasonic or other TV's, and can shed some light on whether switching to component video might work, or can offer any other solutions. Any insight (or sympathy at this point) would be greatly appreciated.