I need to know exactly the same. Did you find out? The manual says to press the "tone" and "standby/on" Hold for 3 seconds and supposedly a prompt for confirmation shows. This hasn't happened. Nothing has reset.
My problem is that I am using the 7.1 analog inputs, and the amp routes everything to the back surrounds. I checked the DVD player and correct signal is coming out of each out. So, I am hoping a reset fixes it. Unless you have any other advice?