Just a general question.... There are many different sound cards out there. From one's built on the mboard, through to expensive SB Audigy ones. Say they all have the digital spdif connector. well, is this just a pass thru socket passing the DVD code from the disk to the external amp, or does the sound card do any work to this signal ? Does the make/model/spec/quality of the sound card have any affect on the data stream you get from the spdif socket ?