I've only had the vehicle for three days now. I'm very impressed overall, but noticed a small oddity.
I was in the garage yesterday playing w/ the gadgets with the key in the on position. There was a very noticible feedback hum coming from the radio speakers, even though the radio was on at minimum volume. It went away when I shut it off and turned it back on.
The next day I noticed it again, this time while driving. The hum increased in pitch with engine speed. The radio was on when I started it. Again, turning off the radio and turning it back on fixed it.
In my old car (also GM), I'd occassionally experience the same when trying to tune a weak AM station (background hum would increase in pitch w/ engine speed). Not sure if its some sort of shielding issue, or if the radio must be turned off then on again to "degauss?"
I wonder if this is somehow related to the center channel DVD issue, which I understand may be a small short created when the vehicle chimes. The chimes seems to play through the vehicles speaker system, so maybe that introduces some sort of interference as well.