I had an issue a few months ago where the job origin would drift right during a cut. This repeated itself today with other issues. When I finally got tired of it drifting it was about 12" to the right of the origin. This was not a step change but slow change in origin. Last time it had drifted about 9" before I stopped it. Z and Y origins are not changing. Several have suggested there may be an issue with the Z ball nut. From what I have checked there does not appear to be an issue with the ball nut nor have I found any loose wires. The other issue today was the machine went backwards during first two attempts to zero, but only for X. Meaning it went to the right (+ direction) instead of to the left. It even did the same when I tried to move manually with keypad. Shut power off, restarted with same result. Shut power off another time and restarted and it homed without issue. Any suggestions?