2.8W diode laser minimum percent power setting or any laser

As an example, 2.8 W diode laser, what if this applies should the minimum percent power set at?
Reason, I had my 2.8W set at 0 % minimum power and it my laser seemed to be making “hammering” sound as it was trying to laser / etch white tile painted black. Or dose it make a difference minimum % setting?
Thanks