Welcome to TFP! We're going to need more info about your pump/equipment to help. Please update your signature first. Then reply back to this thread more specific details about your pump/motor (type, model, etc). With more info I'm sure we can help.
Also, does it seem like the motor is actually on HIGH, but water itself is not flowing well? Like a partial obstruction or flow problem perhaps? Have you seen a difference in your filter pressure gauge lately?