Spent close to a year doing these methods to try to get the PP to keep up with the Brother to no avail. The spindle accel/decel parameters in the Brother are not accessible even by Yamazen. You will have to manually add lines to the program with spindle speed commands. We finally went with a rotary.The speedios regen a LOT of current when they stop. Probably more than the phase perfect can dissipate. You can probably slow down the spindle accel/decel to make the problem go away, at a cost of some cycle time.