DDJ-400 & Rekordbox problem

Hi

Last week I purchased a DDJ-400 (comes with Rekordbox key) and have run into an issue that I don't know how to fix.  Rekordbox works fine for me (smooth, loads all tracks and everything) until I plug in the DDJ-400.  Once I do this, Rekordbox slows down to an unusable speed, not playing more than 1-2 seconds of a song at a time before the software completely freezes up for roughly 5-10 seconds.   

(eg: play song -> song plays for 1.2 seconds -> Rekordbox completely freezes for 7 seconds -> song starts playing again for 1.5 seconds but faster like it's trying to catch up to where it should be -> Rekordbox completely freezes, not recognizing input from the mouse or from the controller for 5 seconds-> repeat over and over and over)

If I unplug the DDJ-400 Rekordbox returns to it's smooth usable state. 

The controller itself isn't demonstrating any lags or anything, the lights all work fine (even when idle and in use during the laggy Rekordbox uses).

I have attempted restarting my computer several times, checking/updating the drivers, changing the USB port used, used a USB adapter (my ports are USB 3.0).  Nothing I do works.

The CPU meter within Rekordbox is never elevated like the computer is working extra hard either.

My computer:

Dell Inspiron 15R SE (7520)

Intel core i5

6GB of RAM

All of which are above the necessary requirements.

I'm kind of at a loss about what to do and need advice for how to proceed with my troubleshooting.

Thanks!