When I'm connected to the SW1 output I get no red light on my sub which would seem to indicate a lack of signal. When I'm connected to the SW2 output all is fine. Red light goes on which woul d indicate a signal is present and the sub is working just fine. Any thoughts on this?

I'm not familiar with your sub, but do you get subwoofer test tones from the 990 when connected to the SW1 output?

Good call Gonk. I did not get that far yet and it's too late in my house to experiment. Will try this tomorrow and let you know. The sub is very new and it does have the "auto-on" feature when it senses a signal. Hopefully this is nothing....

Confirmed! It's just the sub and it's auto sensing feature. Whew!

Excellent news!