How do I get sound from my Digital Cable box to my Bose 321 or HTIB?

There are a couple of different ways to do this, but the easiest is this:
For watching cable – on the back of your digital cable box you will have an audio output (red/white – left/right). Basically all you do there is connect that output to the input on your GS system and when you are watching anything on the cable box, the sound will then come through the GS.Your TV may have an audio output as well, if it does, then all you do is connect an audio cable from the TV audio output to the GS input and from there anything going through the TV would come out through the GS. I’m not a big fan of doing this though because if you watch your TV through Channel 3, it converts sounds to mono, even if you have a stereo TV. The best bet is to just run audio out of your sources like your cable box, VCR, etc. directly into the GS. Hope this helps.