What bestbang4thebuck's saying is that it is theoretically possible for the audio portion of an HDMI cable's signal to pass through the 990's DVI switching, assuming that the two DVI-HDMI cables are terminated the same way and that the audio conductors are terminated to some of the extra pins in DVI's dual-link connector. What does that get you? Not very much, actually - the 990 doesn't actually do anything with DVI input signals (just steers them back out, unaware of the content of those signals), and the HDTV (direct-view, rear projection, or front projection) isn't really going to have much use for the audio once it gets there.