Hi, this switch under the light grey ,square plastic button seems to be “tired” from everyday use : It switches the speed of SK2 digital leslie from slow to fast speed only every now and then. As you know, this switch is used several times during a song, that’s why it is so important. So the problem is the switch itself, not the plastic button. And yes, I have the “half moon” switch connected, which works fine, but still I must replace the original push button switch.