Reply to M Audio Xponent/Torq 2.0 Question

Hey guys, sorry for this question, I'm kind of new to the community . I was wondering if anybody by a chance knows about the M Audio Xponent and Torq 2.0, if they could answer an important question. As I have been learning and using the M Audio Xponent along with Torq 2.0 for the few months that I have had them, I have been having some trouble pre cueing my tracks as I am mixing during my set. On each deck of the Xponent, there is a headphone button, and I assume that is to put the sound of that deck into the headphones so as the cross fader is moved all the way over to the other side of the deck, I am able to hear the other track on the other deck through the headphones without the dance floor/master speakers hearing it. I have done pretty much everything I know how to do. I am sure it has something to do with software that I am doing wrong, and not the hardware. Any advice?

Thanks