Aha. Didn't realize the Traktor had its own sound card. Thought it was just a controller panel.

Yeah, if you're getting stutters in its audio output, and you're sure you're configured to use it as the audio output source, then its audio drivers are the first place to start looking for problems.

It seems like the kind of device which would have its own ASIO driver already (thus relieving you of the need to use ASIO4All). If so, somewhere there should be settings for its buffer sizes, which control the overall latency. Sometimes increasing the buffer size, which increases the latency, will reduce the chances of audio glitches. Which may be what you did already like you said at the top of the thread and we're going in circles now. :-)