Thanks, I will play with it. Can't do it right now. I changed the Wii sound setting from Stereo to Surround, but I guess have to figure out how to tell the receiver to covert the signal to 5.1. I looked in the menu settings to see if I could change the audio signal input, but it is on Auto detect, and surround mode is turned on.
The cable coming out of the Wii has 5 plugs - 3 for the component video, I believe, and 1 red and 1 white for the audio.
EDIT: According to Batpig's website, there is a button called "Standard" on the remote that changes the sound mode. I checked in the manual and all the pertinent information is in the section "Selecting a listening mode" on pg 26-28 on the 791 manual.