Reply to Numark Mixtrack Pro

my issue is that I can't get any sound out of my headphone cue (The Mixtrack Pro I have came with DJ intro and my headphone cue works fine for that) ! ... I have traktor PRO 2 installed everything works my set up is as follows: Audio device: Speakers(2-Mixtrack Pro) and Built in sound card: Speakers(2-Mixtrack Pro)