Hi,
whats your Latency Settings from the Pioneer tool?
How many Services / Userprocess are Running Courently on your HP Envy?
Whats about your USB Drivers, are they from Stock ore microsoft publisher ?
Your Issue musst be your Personal Windows / Traktor Settings and not realy the Device.
please Follow thes Tips from NI first!
http://www.native-instruments.com/knowledge/questions/847/Windows+7+Tuning+Tips+for+Audio+Processing