I have a Numark NS6 with the updated driver v3.2.0. I plug it in while DJay Pro is open and it takes about 1-2 minutes to recognize the controller. Then the Numark logo appears and fades. I was able to use it once for about 4 minutes then it stopped. It is no longer visible under MIDI or in my preferences as a device. I can turn it off and back on and it will do the same thing, turns on but is useless and then disconnects. The one time I did have it working the main output kept reverting to built-in. It would configure audio engine then revert right back to built-in after I hit play.
Is the Numark NS6 still listed at device preferences > “General” > “About” once it stops triggering the software?
If not, your Numark NS6 is defect. In this case, please kindly contact your seller to get it repaired.