What do you mean by run 1 speed and can't adjust it? There is a white knob on your controller go from small to large but that doesn't mean when you turn it to the large end then your pump will run max speed. It means that the pulse is longer, when the white knob on the smaller end, the pump pulse faster.
You need to turn that white knob counter clockwise till stop. Slowly turn the knob a little bit at the time then stop and observe for at least 1 min. If you see any wave then turn it again. FYI, the white knob are very sensitive, it you make a large adjustment, you will NEVER get the wave you want.