Could you list the names and model numbers so we know what equipment you are using? Each brand has their own quirks, so people like to know what equipment is being used.
I had the exact same problem with a bose lifestyle 25 system. It only happened on the analog cable channels (1-99). My particular cable box has 1 digital out and 1 set of analog audio out (I think... to be honest I didn't care enough to check), so I just ran the digital audio (optical wire, in my case) to my Bose receiver for surround sound on the digital channels (which worked fine), and the analog set to my TV speakers (for the basic cable channels, where audio fidelity is blatantly disregarded by the cable company anyways). It's a simple setup, so the bose only needs to be on when I am actually using the speakers, since it doesn't do any video switching. Everything works fine now, and even though I am not getting dolby pro logic surround when watching basic cable, I have yet to lose any sleep over it.
