…been using my Shapeoko for about 2 years now and have never had any issue with disconnecting during a run cycle. After downloading Carbide Motion v579, the first program ran I had a disconnect after a 1/4 of the cycle.
Usually when this problem arises after a period of successful use it is caused by the carbon brushes in the trim router wearing down — please try replacing them — if that doesn’t work, please let us know about it at support@carbide3d.com (mention that you already tried the brushes so we don’t ask that you do so again).