Reply to using other instruments with the s4?

Hi.

First post here.

I was wondering if there is anyway to be able to import my drummers electronic drums to a separate deck so that I can add the traktor 2 effects while he plays along with the mix.

does anyone know if this is possible and how to do it?
please help...

I tried to connect it through the rca jacks in the input channels both decks c and with no success..

also tried to to put it in the mic spot but would know how to get a seperate deck for it..

anyone please help.
I also have a midi-fighter and a behringer bcr2000 if this helps at all.

we just want to be able to live mix the drums into a seperate deck if possible

thanks so much for any help