DDJ RB problem with Headphones sound (distorted)

 Hi there, I've had my ddj rb for about a year now and it's been a few months that the sound coming from the headphones (cue) sounds distorted even though it used to work fine. I've tried different headphones so I don't think it's a problem with the headphones themselves but rather something to do with the aux plug or something. I have no idea why it suddenly started not working.