"If I could run the Sirius straight back to the processor optically instead of into the X-fi box, I think I would end up with a bit cleaner signal than the audio cable plugged into the X-fi, do you agree?"
I guess I didn't word this very well. I wasn't trying to suggest the signal would improve after the source, I was only hoping that by bypassing the X-fi altogether and using optical cable all the way to the back of the vehicle near the amps and processor, the signal might not suffer as much during it's 10' long trip.
Anyway I have just ordered one of these this morning:
It will be here next week and I will experiment with my current MJS-SCC1 and see what happens. I'll let you know if I am looking for one with opt. out and we can go from there. Thanks.