I bought a workerbee CNC machine from Yuyong Industries. The build went well and I can jog the machine around the table using mach3. But there is a knocking sound coming from the motors which is also audible during travel. And if I load and start a gcode (the roadrunner) the gantries shake and and the motor noises become quite violent. I think the problem might be with the controller (NVUM V2 4axis) or the power source… I did notice that the little green light on the power supply was dimming slightly in sync with the knocking noise from the stepper motors. I’ve gone through the same tutorial 10 times over now and I’ve got it all hooked up right… I’m lost