Never noticed it on my previous 970 nor the receivers I used as preamps. Don't have any dimmer switches in the house, and I have DirecTV. I'm really at a loss of how to 'fix' it. My amp is a "B" stock, don't know if the problem is with it. I'm going to try to hook up my Oppo direct and see if I still get the hiss (didn't recall it with my 980 though).