I have a Marquis spa with a 2 speed motor(220V). The motor does not go on into low speed from start-up. If I press the start buttom twice I can get it to jump into high speed. From High speed the pump can go into low speed with no troble and back to high again. Is the motor inability to go to low speed from start up a motor or control circuit problem. Any suggestion on how to determine which if both are possibilities.