My name is dj habboos,I'm working on this project on pioneer djm 2000 trying to fix in serato sl3 box into it,it works fine and I used wires but later want to change it to rca and through that everything went off no audio coming out of it,but now I've done some works on it so I'm getting audio out on only channel 3 and the channel 3 is just from the negative side of it,pls what can I do next.

 

Welcome to AAC!

Your first step is to source the service manual, more importantly, the circuit schematics.