The problem of manual loop in and out on xdj-xz

I Have a manual loop problem here. when i press in loop and press out loop my current playing song bpm goes wrong. Example my current song bpm is 128 when i press in and press out my bpm will random jump such like 140bpm 80bpm. Even i press quantize also not work. I try to update firware and driver as well but still no solve the problem. Whats wrong with this? I need help...