Reply to S2 Timecode + Audio 6 Headphone Cue

I've got my 1200's connected through Traktor with an A6, using an S2 as a midi mixer. Everything's working fine, but I can't seem to get the headphone cue working. I have my turntables plugged into the 3/4 and 5/6 inputs on the A6, with the 1/2 main outs going to my monitors. The S2's only connected to the computer via USB. My headphones are plugged into the headphone jack on the A6 but the only thing I can get out of them is the main out. I don't have cue or headphone output settings in Traktor, just "Output Monitor" "Output Master" and "Output Record".

Any ideas? I know some of you have the same setup.