My stepper motors are randomly and frequently stalling while using the Pokeys57CNC controller board, any idea what could be the issue?

I would suspect that the velocity and/or acceleration is too high for the amp setting on the driver. Consider increasing the current amp setting on the driver is the motor can handle the current, or decrease the velocity and/or acceleration. You might also want to check to see if you have any mechanical binding on the machine. To check, remove the mechanical drive mechanism so the axis slides freely and slide it from end to end to feel if you have any tight areas or binding. Additional Information: