Audio Driver Standards Issue

I just got NTrack Studio and it had been working fine with the default MME audio drivers.
I was reading the manual and it was saying that a better choice was to use WDM drivers so I went into NTrack and selected that as the recording medium at the bottom of the VU meter.

A few boxes came up about resetting sampling rates etc or some such.
Now whenever I click the ā€œSā€ solo track button the sound makes popping noises.
I tried to go back to the old MME choice, but it still does it.
Anyone have any idea what this is or what I should do?

EDIT: I have a Soundblaster Audigy 2 soundcard by the way

EDIT: Hmmm, it does appear to be running a bit faster besides the popping sound though. I wish I had a clue what I was doing.