UPDATE - HDMI Switching:

After playing around with switching sources and entering/exiting the OSD I can only say this:
The issue I'm having is pretty random (but not too frequent). Most of the time the picture flakes out while audio is still present. Most of the time the unit will recover if I switch between sources a couple times, otherwise a power cycle of the unit takes care of it. My HDMI sources are all pretty current (TV < 1 year old, HDTV < 1 year (NVIDIA card), oldest is PS3 at about 2 years old). But I've never had any issues before. This unit just seems to struggle a bit making the connection (usually audio comes on a bit after the video). Nevertheless, once a connection is made all is good. This 975 plus my Axiom ADA-1000 does a damn fine job of rocking the house. I'd have to call the 975 a bit "quirky" but still wholly satisfactory.