deathbychuckbut isnt rca also digital audio input, when used as S/PDIF? From another persons perspective i guess the rca could be suspected to be a re-used Red 75ohm jack from a component video input, afterall. :P Or just a digital color coding scheme the repliant isn't familiar with.., So i should say; certainly an understandable question, just based on the facts of observable appearances alone. :P
Caizthat is to say maybe from the replaint's perspective, some unfamiliar digital transmissions scheme, like S/PDIF was used but with two channels, perhaps to cut down on jitter..?