Got faucets that screech when you turn them on? Or pipes that hum when the water's running? Your house isn't haunted. Chances are you have a bad main-inlet valve or a bad pressure-regulator valve. There's only one place water enters a home. If every faucet groans and howls and the same noise is heard all through the house, you've got a bad main-inlet valve where the water line enters your home. Here's what happens: Over time, the rubber gaskets of any plumbing valve can become brittle. When you turn on a faucet, water rushes in, passes over the gasket and acts just like the reed in a clarinet. The pipes carry the sound through the house to every faucet or fixture, making it hard to pin down the source. If every faucet makes a similar noise, check the main-inlet valve, but if you hear a screech at only one location, check the gasket of that particular faucet. If you're handy, the repair can be done with a few basic tools for less than $10. Got faucets and pipes that moan and groan? Spruce up those valves and you'll be the only one singing in your shower. And that's the On The House tip for today.