The first M600 works great. All I add is the m600. The printer retracts, raises up off the bed and then moves over to the edge of the printer and retracts some more to move the filament out of the nozzle. I then manually add new filament and hit the button. It moves back to where it left off and resumes. I don't add any more to it then that.

On on the second m600 it just spits out filament. The first works, just not the second!