Midi/audio configuration with Pioneer XDJ-RX

I haven't yet set the aggregate settings within Mac utility so I can record a mix with my XDJ-RX.Is there a way using this method to have the XDJ-RX's internal sound card occupying channels 1&2 (Including the headphones) but at the same time using e.g 3 & 4 of my external sound card to record.Before I try out the settings I was hoping someone might have this down already.