Problems with audio DDJ 400

Hey,

I got my first ever DJ equipment today, it's the ddj-400.

I registered to Rekordbox and everything went good when I opened it for the first time. Then I closed the program to download some tracks to play, and when I opened the program there was no sound at all. I checked that everything on the controller itself is on, then checked that the audio settings on Rekordbox are correct, but still - nothing :(

However, when I change my "Windows Audio" from "DDJ 400 WASAPI" to my speakers, there is sound coming out but I can't control the volume of the tracks from the controller and can't control the eq... tried every solution that I found but nothing works...

sorry that it's long... really hope to fix it and start DJing...

Thanks

David