i am having problems with using an mpg and mach 3. i can get it to work properly and it works well, but mach 3 will intermittently switch itself off, or switch axis on its own. for instance, i can select x axis to jog with mpg, and crank along forward and reverse but the software will switch itself out of the selected axis on its own, kind of slip into neutral until i select the axis again. i have tried different versions of mach 3 , same proplem. mpg is connected to opto isolated breakout board, pins 13,15.