Toshiba sd-h400 (TIVO) Audio Failure

I purchased the Toshiba sd-h400 TIVO box almost a year back.
Recently the audio output started failing. I checked all cables
and all outputs (Digital, RF out, etc.). None of them have any sound
output.

If I unplug (Power) the box, leave it that way for some time and
then power it back on, I get the audio back. However, it fails again
after some time.

Has anyone else noticed this problem and/or know a solution?

Also, has any one made use of the warranty from Toshiba.
I still have a month more of "parts" warranty. The 90 day "labor"
warranty has expired. Is it a pain to send it in and have them
fix this problem?

Thanks!