Midi problem

Unable to get my midi controller to work. I currently have it set up, midi out of the controller to midi 1A of the MPC. Then out of the of 1B to midi in of the rack. I know the controller works because when I put it in the rack directly, it plays. Any ideas guys. I've had it set up exactly this way before but now for some reason its not working.

as a good place to start think what you changed in the setup to make it stop working ,secondly does the mpc still play the module from its own pads?...

Yeah, i switched the setup around to the 2 side and it works...which means I have fautly midi ports or some shit.