I'm looking to hookup my empeg with my factory head unit as well for use of it's tuner and stock CD player. Now that it's getting colder out, I sometimes run into the "hard disk not found" error, so it would be nice to be able to use my factory head when the empeg is out of the car.

That said, I'm looking for a Sony XA-39II. Crutchfield doesn't have them, but they do have the PIE MPSS-4 as firefox said. Anyone know what happens if both my factory head and the empeg are on? Will the MPSS-4 have a "master" input that would take precedence? A crutchfield advisor didn't seem to have an answer. They told me, it may play both or may switch back and forth between the 2 very quickly.

Do any of the Sony XA-39 owners know if there is a "master" input on it? Anyone know where I can find a XA-39 now?

Thanks all!