Crackling, Popping, Static Noice - Roamio & Denon Soundbar

I just bought and setup a Denon HEOS soundbar with my TIVO Roamio. When I change channels or fast forward/rewind, there is a static/crackling/pop sound.

Denon is stumped, so I'm hoping this community can help. What might it be?

I tried:

• Using HDMI and Optical - the same problem on both
• Other set top boxes (e.g. cable) and they have same problem all be it less pronounced

Thanks for your help.

Crackling, Popping, Static Noice - Roamio & Denon Soundbar