For This u can in crease a bit. I believe default is 20khz, can increase somewhere up to 40khz. this give u quieter motor spin as it passes human hearing range. but this can heat up the motor a little and less efficient. Depends on the motor u use u can actually gain more stability(less coggy) not too sure if true.
{source:Benjamin, Endless sphere}
start up boost is for initial current feed for stand still moving. it’s like initial foot push for motor to start spinning, but electrical. Thats all I know