You can only set it to work with Master output or a channel, BUT it will give you a loud feedback sound if you route the output into the RMX and then back to a channel. By using the master out to your amp or speakers, you can put it between those but then you can't cue the effect before firing it, it will go out live to your sound system. I have tried 4 different ways with the RMX-1000 and all the same results. Search Youtube for RMX with DDJ-SX and you can see and hear the results.