I had a similar problem with my Kitchen Aid. The switch is not actually a switch but rather moves a lever that operates two things at the back of the mixer: 1) a simple lifting copper arm that makes a contact to provide power to the system (electrically this mixer is just on or off) and 2) The lever also moves the entire back control board forward and back. There are two long screws at the top of the control board that are spring supported to allow for this movement. There is a governor on the shaft of the motor that pushes against a plate in the center of the control board. The farther the switch moves the control board back the further back on the shaft the governor can go and the faster the machine can go. In my case the screws holding the control board had come loose allowing the governor to go all the way back (high speed) at the first click. Take the back cover off and see if the two top screws need to be adjusted (tighter and the mixer starts slower (or not at all) looser and is starts faster and...