I have a k40 laser, the board was an m2nano. I upgraded the board to cohesion 3d with smoothie ware. When I plug in the cohesion board there is a noise coming from my machine that wasn’t there before. The noise sounds like a whistle/buzzing.
It’s fine. It’s just the steppers being held in place. My CNC machines do the same thing. Nothing to worry about.
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Ok. Thank you for the help.