Flojet pumps have a diaphram pressure switch. Assuming you have the usual 55psi 3.7(from memory;-) gpm pump, the pump will cycle frequently to maintain pressure. The more demand, the more it cycles until the demand exceeds the capacity, then it stays on.
So is it the noise or is it a real problem? If you want, you can add an accumluator which maintain a more even flow and reduce cycling. Its like a pressure tank for a well pump.
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Be satisfied with your opinions
and content with your knowledge.