We have a shower in a 2nd bathroom that has a loud squeal whenever it is used. It seems to be temperature related as it does not make any noise when running cold water. But as soon as any warm water is introduced it squeals. It sounds like the noise is at the shower head. I've changed that out with no change. Any idea what's going on?

What type shower valve do you have? One handle or two knobs? What's the brand name" how old?
Squeels, groans and fog horn sounds are caused by something vibrating in the valve body. Let me know what you have and we'll see about grtting it fixed. Regards, Tom

I'm not home to determine what brand it is but it is a single handle and it's around 13 yrs old. My guess would be it's a moen or delta. According to my wife it's been making this noise since we put it in... nah, let's not go there! :)