Try downloading the prusa edition of slicer. I keep repeating this but I can’t stress it enough about how it’s “changed” the machine. I had simular issues with noise that you did. And it has quieted down quite a bit, as long as I’m not printing something with a voronoi pattern ( lot’s of z hop) the machine is pretty quiet. It sit’s on my desk and I no longer have issues with it running while i’m trying to concentrate. When I slice with the old slicer or Cura it get’s loud again.
I guess I should also mention that I export the gcode to repetier host and run it off usb, I haven’t tried running of the SD card in a while.
Let me know what you think. It’s in the drivers package. You’ll get a model of a cool spitfire too, so that’s a plus!
Also remove the auto bed level code.