split cue is probably on...check your que switches and your headphone plug.

It could also be your connections. I had a similar problem when I first got CDJ 1000 MK2s (I sold them for CDJ 200s, crazy..I know but I actually like my CDJ 200s better) and a Vestax PCV 275. The problem was the connections. Check to make sure the RCA connections are secured, not super tight but not loose either. Loose connections can cause only one speaker or headphone speaker to work. Just tighten them up a bit...unplug them and screw them back on to your mixer.

The connection isn't being made on one of the channels. Try a different pair of headphones. If it still does it, it's internal, if not, then it might be the headphones. Try the headphones in a different sound system. If the same problem occurs, switch headphones. If it plays fine, then you might be in need of an adaptor, because oddly enough some mini-stereo and even RCA (but less so) connections are slightly more seperated than the norm, resulting in only one channel being connected, or in the case of mini stereo, sometimes they have 3 channels instead of 2 (just look at how many horizontal lines there are on the plug). If all of the above fails, contact vestax.

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