Djm 450 recording to laptop

I'm recording sets straight to my mac onto recordbox. I did one set of around half an hour and got a clipping noise over the top. With trim levels at 0db max volume a little over half way and faders all the way up. Second mix I have done I got the same until about half way through the second track the sound went completely and I just got this sort of phasing noise for the next 45 mins. Any help?