Thank you for writing back to me. I have not heard of a situation like that but I guess it is possible if the water pump has to work a bit harder to push the water through another device. You can insulate the pump part as long as the motor part is outside in the air to keep it cool. but it has been my experience the motor part usually makes more noise than the pump part. Maybe something got past the strainer and is stuck in the impeller of the pump? Maybe the pump is going bad, bearings? Hard to say without looking, but under normal conditions it shouldn't be noisier.
Marcus Miller, President