I have had a deep sounding hum coming from my hot and cold water bathroom faucet (2 handle) and it gets very loud. It goes away when I open the faucet more. It mainly sounds when I have a low level of water coming out. I have two identical Pfister faucets making this sound in the same bathroom. I would appreciate your thougts. Thank you.

It can be one of three things:

1. Dirty Aerator. Remove aerators, clean it and reinstall.
2. Kinked flexible water supply lines under the sink. Get under sink and with hour hand reposition hot and cold flex lines. Also, PP faucet has 2 small flex lines that connect Stems and Spout. Move those too
3. Angle Stop. Close and Open h/c water angle stops.

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