I'd use some small relays for audio signals, not the big beasts with big windings inside. You can get some tiny dpdt 12v relays from digikey, last ones i got were under $10 each. some specify whether they have an off state between no/nc modes, I'd think you'd want one with a smooth transition to eliminate pops.My first approach was to build an N-channel mosfet setup but the price would be to steep for my $40 dollar blutooth setup. Solidstate relay's also run around 50 a piece... eek!
Dragonrage - Do you have any experience with using a standard spdt bosch relay for audio? I am trying to stay awayfrom the clipping sound is possible