I bought a black buck 8M driver for my laser engraving machine. The laser I have is at 2.5W and should have as maximum 9 volts and then about 1.1 amps. Has set the maximum limit of 8.3V to the driver with an electronic controller. The driver is controlled with uccnc with pwm signal 0-255. Already at 40 the laser gives full power 1.1A. becomes very strange engravings. Why is it like that? Someone who has a solution?