Installed the CNC fusion delux #4 kit with keling 387oz/in motors on my Micro-mark X2 mini-mill. Using mach 3 I can jog all the axis's fine but after about a minute or so the x-axis slow jog doesn't work. I am using a Shuttle Pro 2 for jogging. I switched the X axis cable to the 4th axis input and it slow jogs fine, then switched the X and Y motor inputs and the Y-axis has the same problem. So its not the motors or the cables but the problem appears to be with the X input on the G540. Has anyone encountered this problem before? I have the unit cooled with 2 12v computer fans so overheating is not an issue.