Drives my wife nuts when she comes in and the TV's showing one thing while the audio is doing something else (watching TV while a CD plays, for example). This can be done even with the 990's video switching in the mix, actually, as long as the audio in question comes from an audio input (CD, tape, aux, phono, or tuner). You simply select the desired video input on the 990 and then the audio input - the video switching stays at the last video input used.
That reminded me of "dueling remote controls" from my college days, when a roommate had a Yamaha receiver with a learning remote that was set up to control the entire system but also had his TV remote sitting around...