Still looking for answers. I posted the following thread in the TV and soundbar sections...
I've got a Polk Surroundbar 5000 connected to my Sharp Aquos LC-42D64U via digital optical cable. I've got my Xbox 360 connected to the TV via HDMI. I was not having any luck getting sound through the soundboard when the tv was switched to the Xbox input. I have had to run a basic audio cable from the audio out on the tv to one of the non digital inputs on the soundbar. Obviously, the sound is not great when playing Xbox. It sounds great with the digital cable though.
I tried every possible menu option I could find on both the TV and the Xbox before running the aux cable as a temporary fix. If anybody could help me get sound through the sound bar from my hadji xbox while using the optical out on the TV I would greatly appreciate it.
Polk customer support and Crutchfield technical support were no help.
It's not the optical cable as it works flawlessly with the other inputs.