I have a new Price Pfister faucet in my bathroom that makes noise when turned on low, a very loud vibrating noise. It sometimes makes the same noise when almost turned off. The problem started whent the faucets were just several months old. When that bathroom was redone the plumber removed the copper anti-knock chambers. Most plumbers say those are not needed. I'm re-doing the second bath and refused to let them remove those copper pipes on the shower and sink. Three plumbers have not been able to solve that noise. Is it the Pfister faucets?