I am thinking about buying an API a2d, which has AES/BEU output, as well as s/pdif coaxial output. I am trying to figure out the best way to get the output into my Mac Pro. I only need two channels. It would be great if I could save some money here. The Mac Pro has its own optical inputs, so I could just convert the s/pdif coaxial output into s/pdif optical output. But my fear is that the Mac Pro's optical inputs don't have a way of syncing with a clock. The API a2d doesn't send a clock signal either. So would I need to get an interface that is capable of producing a clock signal so that the output of the API a2d is synced with what's going into the computer? Any recommendations? Thanks in advance.