Dewald_visser, it looks like you hit the nail on th head. The control board is pretty simple, and there's one 3300uf capacitor on the output drive for the motor. I didn't have an exact replacement so I added a 1000uf (I canibalized it from a car stereo!)in parallel with the 3300uf.
It's holding speed perfectly now, and the adjustment pots are set closer to mid point now. I'll run it like this until I can pick up a replacement for the 3300uf.
thanks fo the assist, Brad G.