Originally Posted by
James Newton
There is a maximum set by the pulse rate that can be generated by the PC and handled by the stepper controller. If you need 16 pulses to micro-step through one full step, you have to generate 16 times as many pulses in the same time to turn at the same speed as you would if you were full stepping.
Having said that, what you describe your motors doing sounds more like mid band resonance, and that usually improves with /higher/ microstepping.
So try it, and if it gets worse, add mid band resonance compensation instead.