I had a new Price Pfister, one handle kitchen faucet, with spray attachment on pull-out hose installed by a plumber. Before he left, I quickly turned on the water to make sure it worked... no problem noticed. The next day, when using the faucet on full power I noticed a loud, high pitched groaning noise. I called the plumber back out to fix what I thought was a problem with the way he installed it. He assured me it wasn't his fault. He showed me that the noise stops when the sprayer is activated, so he thought it was the spray head. I called Price Pfister and told them the problem, and that the plumber thought a new spray head would solve the problem. Price Pfister agreed to send another spray head (under warranty). While waiting for the replacement part, I did some research on-line and came across many sites (like this one) where others have the same problem. After 5 weeks, I finally got the part. After installing the new spray head, the noise is as loud as ever. Help! The noise is driving me crazy.