you really shouldnt need to use a mixer with the m-box. I dont own an m-box but from what i know it has focusrite preamps already in it. You can run your microphone or insturments directly into the m-box then rite into your computer. Running it through a mixer just adds more signal path, which is degrading the signal. I would just scratch the mixer and just run the m-box for preamp and conversion.

yeah, could you be more specific on how you want things to hook up, then we can help you more, and like perfectwave said you shouldnt really need that mixer.

Ben

Well I'm Using the mixer to get more inputs cause the mbox only has 2

so then you are going to be mixing down before your mbox, which means you'll only have two channels in protools and will not be able to do much with it after the fact. if that makes sense to you and that's what you want to do, then all you need is a pair of TRS cables to plug from the output of your mixer and plug those into the mbox set to line inputs.

Ben