I just had a plumber install this faucet yesterday. Whenever the faucet is turned on after not having it on for 10 minutes or more, it produces 1-3 thumps. I could live with the noise but I am afraid that the resulting vibration may cause future problems. I have Foundations Single Handle Kitchen Faucet With Spray, model # B3310LF. From reading other reviews, this seems like a design flaw.