Two Outputs, One Input

MY SITUATION: I have 2 Sony CX230s controlled through SLINK by CDJ software on my computer. As you know, when controlling the order of play of individual songs, CDJ will seek the location of the Song "A", play it and then fade between Player #1 and Player #2 to play Song "B", the next song. Then go to Song "C" and so on until completing my playlist. MY PROBLEM: I have a Bose Lifestyle 12 with one receiver input to handle the output of whichever CX230 is being played at a given time. 1. Must I use a mixer to accomplish this? (I am using this method now and it significantly diminishes audio quality due to the mix of two sources) 2. Or is there some device that detects which CX230 is playing and routs that un-mixed audio to the receiver? Also, how is this handled with three or more CD players?!