Need help with set up!!!

Ok so I just upgraded to cdj 900s and I am running traktor pro 2 software with an external mixer. I can not figure out why but I can not get the connection to work. I do not know what settings my traktor should be set to if that is the problem. I feel like I have tried everything. I have the actual cords, usb from computer to cdjs, rca's from the cdjs to the mixer. I have gotten sound to come out once, but both decks were controlling the same song and all the controls were not working.
Thanks in advance!!

plenty of tutorials on youtube on how to setup CDJs and traktor.

Thanks....I did all that already. I have watched pretty much EVERY video that there is out there. I have installed the driver, changed every setting on traktor that I can think of but I am simply stuck! My cdjs work perfectly with every other feature except the traktor. My cdjs are also able to control the traktor settings perfectly as well, though I can still not get any sound when linked to the traktor setting. Is there something that I am missing?