You need to either use the front panel display or the on-screen display to get into the Model 950's setup menu and assign digital audio inputs. The manual covers the setup menus starting on page 22.

Optical and coaxial digital audio inputs: These can be assigned to any input using the INPUT CONFIG section of the setup menu. You pick the "source" (the input you are associating with the source device), then move down to INPUT and pick from analog or one of the six digital inputs.

Video inputs: The composite, s-video, and component video inputs are fixed to the input that they are labeled for. The component video output works only with the two component video inputs (no transcoding from s-video or composite to component). There is transcoding between s-video and composite, though, and you can connect the s-video monitor output to your TV and have access to all composite and s-video inputs. The on-screen setup menu can be seen from either the s-video or the composite video monitor output.

You mention that you have a digital TV, a cable box, and a DVD player in addition to your computer audio. Can you give us any more specifics? What are the best inputs on the TV? What are the best outputs on the cable box and DVD player?