Cracking sound while using DDJ1000 with 2011 MacBook Pro

When attempting to live stream onto Facebook from my Cellphone, my viewers informed me of a strange sound during my mix. It is a very annoying, persistent sound that appears every few seconds as the mix progresses. This problem has now escalated, as this sound persists even when I'm not live streaming, which is why I need your assistance. This issue is making recording my mixes impossible. Please help...thanks