Actually, you should be able to pass the cable output to your tv and then to your home theater system. I have my Tivo, cable, PS2, etc. all going into audio inputs on my Sony HDTV. I then have one audio cable (l/r) running from my TV audio output into an audio input on my H/K receiver. When I want to run the audio through my receiver, I just have to shut off my TV speakers in the menu on the tv, and then the audio is piped to the receiver and my Axioms.
I generally always leave the speakers in the tv off, and exclusively listen through my receiver and Axioms, so there's really nothing to it. Try something like that and see if it works.
