XDJ RR - Right Deck Cue Issues

Hi, when i play on my xdj-rr with just a usb - there are times when i load a track to my right deck but the play & cue don't work - so I can't play on that deck. I can change the song, but once it happens I have to re-start the whole system - which is not ideal in a club setting.... has this happened to anyone else?