I've been going slow with my CNCd g0704, testing on wood. Today, I decided to try my luck at aluminum. I think I had my speeds and depth incorrect. On one cut it went in too deep, and broke my 3/8 roughing bit, and tripped a breaker, and blew the fuse. When I got everything back up and running, I powered on the mill, and found that the RPM went to 2200 no matter where the dial is set. Has anyone else had this problem? Anyone know of a fix that I can try?