Picking a sound card

I'm on a super tight budget. I'm using the APC40 mapped with a slightly adjusted version of this http://www.djranking s.com/community /showthread.php?t=19872 with traktor.

I'm looking to get a ddm4000 and want to use it in external mode which requires a lot of outputs. The card that intrigues me the most is the m-audio fast track pro, since I want to use it for production as well. Problem is that it only has 2 stereo ouputs... Is it possible to send out mono to turn the 2 stereo outputs to 4 mono outputs to the ddm?

Thanks for your help guys!