At our school, we have a Behringer AutoCom Pro MDX1400. I have read the manual, and it says that the compressor can do "ducking" so you can hook up a mic and music to it using the mic as the sidechain, and then the music will back down whenever someone uses the mic. What I have done so far is have a mic sending a signal through Aux 1 to SC return, (using a TRS cable) and have music go through Aux 2 to the Compressor input (with a TS cable). Then, the output was an XLR cable to a channel on the mixer. (no more balanced TRS's) I have tried all the buttons and knobs in different places. I have played with this a lot and I have not yet gotten it to work. How do you set it up? (what from mixer to where, etc.) And what settings to you make on the compressor. I have tried just about everything I can think of. What am I doing wrong?