How can I change from 12,000 rpm to 6,000 rpm on the cnc?

Hello Snapmaker friends,
I took the trouble to measure the speed of the milling motor this morning. On the left in the table the percentage values that you can enter via the console.
The following input must be made “M3 P…” and of course behind P the value.
On the right the revs I measured with the tachometer!
The touchpanel can only be used from a value of 50%, which corresponds to a little over 6000 rpm.

Unfortunately, you can not set the speed from Luban herraus, which would be possibly something for an update in the settings of the cutter and so on that you could also set the speed there if only in percent but better than not at all!

P.S. The milling motor turns so with me with speeds from 560 rpm to 12350 rpm

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