CDJ 3000 CUE BUTTON

Help! CDJ3000's. When I load a track it autocues to the first point as expected. I press play and the track plays, but on one deck when I press cue it goes back to the beginning of the track and pauses, but on the other deck when I press cue, nothing happens. Everything used to be fine and both decks would go back to the first cue point. I am sure it is a setting but I cannot find how to change it. Any suggestions please?