Got it. I'm about to wire the these. Which of the orange pair and blue pair should go to A, B, C, and D of the center terminal of the selector switch? Thanks.
The black wires on the center lugs of the selector switch are grounds (they need to go to the ground tabs on the RCA jacks).
The white wire on the center lug of the selector switch is the left channel output (it needs to go to the center post of the left RCA output jack).
The red wire on the center lug of the selector switch is the right channel output (it needs to go to the center post of the right RCA output jack).
You can use whatever wire colors for whichever connections you'd like as long as those are the connections that are made.
-PB