actually, I'm geting it now too... with a mouse and with a graphire. I know the graphire sends 50 instructions per second to the computer, so with really fast strokes, you get those things, but I'm getting it with my mouse too, so this is unpleasant... Just never noticed it before cuz I do most illustration in vector, not photoshop... Painter 7 I know however interpolates it's strokes to smooth them out. It's a big reason why its a slow program, even on my P4 2ghz. oh, and I truly dig my graphire 2. They have wicked customer support and warranty service as well.