I am trying to run two separate Dolby Digital sources to the AVP-9080(DVD, Digital Cable). My problem is this: I cannot get sound from both sources when both are connected to the pre/pro. One component is hooked up via digital coaxial, and the other via optical. However, I can get Dolby Digital output from ONE component when both are connected to the pre/pro, BUT only the component that is connected via the digital COAXIAL cable.(Both components have both digital coaxial and optical outs) How can I get both sources to cooperate with my pre/pro? Any ideas? This is driving me nuts.