I recently upgraded my home audio and video system to surround sound and HD TV. My HD service is from Comcast and I'm using a new NAD t773. Everything works fine from both, except that when I'm changing channels from Comcast channels with normal audio (based on what is displayed on the onscreen menu) to dolby Comcast channels (HD and otherwise), I get a "pop" (split second white noise) occurs across all of my speakers. Note: I only get the pop going from "normal" to "dolby" and not vice versa.
I've had Comcast change out the cable box and still have the same problem, so I'm beginning to think it is a problem with the receiver.
Has anybody else heard of or experienced similar problems?