@ Hadi El Sabaa maybe the hard drive went to sleep,was the looping track on the cdj linked or on the actual cdj with the drive plugged in? this happened to me a while back ago but i think it was because i have a 2TB loaded almost completely with music which makes it slow and it stopped when i was using the other cdj linked not the cdj with the drive plugged in did you update the firmware to 1.5 try that if not.that all i can think of,good luck