The geared motors usually have a lot of backlash. Do not use them, unless you have a good method to compensate from that.
If you lack torque, you could go for 1/8 step instead of 1/32, won’t make any difference in terms of quality, but will improve torque.
But as Ryan stated, if everything is set up correctly, you should have very little force exerced on the machine, it should cut through wood like butter.
Try different feed speeds, different cutters.
It looks like you’re using the same spindle motor as mine (brushless 500W), so I guess it is running at 12 000 rpm. Try different numbers of flutes, to lower the feed speed, the spindle speed and once you get the less audible noise, increase progressively the path deepness. Each machine have different sweet spots, these spots depends of feed rate, spindle speed and many other things, take a look at this great article which explains in detail how chatter works: