Hi !!
I changed the stepper1.setSpeedSteps( 2000 ); // Speed when moving home to 20000 and it worked perfect !
I placed an order for some DRV 8825, as you said the TMC are just quiet in microstepping.
I also will also order an motor with 30:1 gear ratio to get the speed up a bit more, unfortunaly they were out of stock now, https://www.omc-stepperonline.com/precision-planetary-gearbox/nema-17-stepper-motor-l39mm-gear-raio-301-high-precision-planetary-gearbox-17hs15-1684s-hg30.html
"You could use microstepping. There is less noise, but it will be even slower - you must use higher steprates."
How do i use higher steprates?
Maybe this motor with the DRV8825 and microstepping will be a bit more quiet.
Best Regards !