Are the jets open? The center of the jets turn to adjust the pressure of the jets. If this is not the problem, there may be a problem with the impeller in the pump assembly. If you here the pump turning and not buzzing, it could be an air bubble in the suction tube. This tube is the one coming from the front of the pump, if the pump is higher than the tube coming from the tub, or if there is a high spot in the tube, an air bubble is a real possibility. If the tube is level with the pump, there should be no problem with air bubbles and the problem lies in the top part of this paragraph.