I been having problems regarding sound drop issue with traktor pro, after exchanging emails with NI but seems that no direct solutions for it.
Here comes a simple solution and currently it's still working fine for me ( please don't quote me because I'm still a beginner)
Go to your setting, select users, under login, you should able to see a check box under Native instrument. Go ahead and un-check it or delete it away. But every time when you load your traktor, it will take longer time den before.
By doing this, I believe that you are actually restarting a fresh new traktor every time you reboot your computer. The check box are leaving information inside the system so you are not totally logout.
Hopefully this will help