Hi djdejf,
If recommendations from RoJeC don't seem to solve the issue, it might be something as simple as a faulty USB cable. So try swapping that out as well.
Also when you are trying to scratch with the software crossfader is the movement on screen slow or is it that the fader curve is not set sharp enough for scratching?
You can adjust the curve in the settings for Cross DJ (this is a shot of Cross so it may look a little different):
Screen Shot 2018-05-26 at 10.16.43 AM.png
Notice that the fader bar underneath where it says "Custom" is filled orange or all the way to the left. That is how you will want the crossfader set for the sharpest possible curve.
Regards,
Adam @Mixvibes
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