problem recording from djm750mk2 to record box using a mac os x 10.9.5 computer.

hey guys
i was wondering if anyone could help me over come a issue im experiencing when recording from 1 x djm750mk2 and 2 x xdj 700 media players using export mode to record box using a mac os x 10.9.5 computer.
The recording wave file apears in record box but there is no sound at all when i play the recording in the record box player.
A step by step recording set up guide would be very helpful .

Thanks Todd Hellyer .