I have Dish Net. When I just tried this, I happened to be playing the adult alternative rock station. not Sirius, but one of what dish net calls their "CD" stations. It's kinda screwy the way I have it routed because the optical port doesn't work on the PVR 508 and I don’t have HD or digital in my area. So, I run stereo analog from the 508 into the HK's video 3 inputs. I can then select video 3 on the HK and play whatever channel the 508 happens to be on through the HK’s second zone to the 80’s. Make sense?
