I spent a fair amount of time chasing down the rattles on mine. Most came from the covers and some tweaking, bending and spacers eliminated them. Another source was the handles and knobs. I removed the axis cranks since I always run CNC under MDI or program and tightened the way lock handles and it runs fairly smoothly now. I do need to tighten the splines just a bit.

JT, I believe I did use 120hz on the VFD settings.