Krell HTS 7.1 with TV

I have a couple of problems with my Krell HTS 7.1
1. When I change the TV channel or when commercials change back to the TV show the relays in the unit blanks out and on and it takes about 3 seconds to do this. So my question is should this do this and how long should it happen.
2. I also have Channels blank out with no sound, but if I change the channel there is sound. What causes this?

Anything you can share would be great.
Go to the AVS Forum and there is a whole section on audio pre/pros and the Krell HTS 7.1