I use my NAD T742 for everything in my living room - regular TV, DVDs, CDs, iPod. I switched off everything and went to bed last night, and everything was fine. When I turned on my NAD, TV and cable this morning, I can hear a fairly loud buzz when using my 742. It doesn't matter if it's tuned to video, CD, DVD, FM or SAT, the sound is present in all modes. My 742 is maybe three years old, and I have no idea how to troubleshoot. Maybe it's my PSB speakers? Any ideas on how to help before I carry it in to a dealer?