Reply to S4/Win7 bizarre jog resolution/latency issues. Insight welcome!

So I ran latencymon and saw my factory installed graphics card was a resource hog. I've disabled it in my device manager and immediately noticed very "gritty" sound when scratching. I usually run the script to shut down all unnecessary services. I then noticed that there was no "grit" when in MIDI mode. I then tried the DJTT NHL map and VIOLA! Best sound I've ever had at 6.7ms latency.

Why would the default map still have terrible sounding problems? Bueller?