Bitrunner minimum spindle speed

I am running a job that uses three cutters with three different speeds. The bit runner starts the router for speed 4 and speed 6, but on the 60 degree engraving bit the speed is set to 10000 in CC. CM says set the spindle to speed 1. With that, the bit runner does not start the router. So I have to unplug the bit runner and plug in the router and manually start it. All works well then.
So what is the minimum RPM to get the bit runner to start the router?

Did you configure for a BitRunner or VFD in the Setup Wizard?

I texted with Oscar with more explanation and sent the cc file I will check the configuration when I get back to the machine but it should be the router.