[terry and jo]

In all fairness, I am the least qualified to give a really definitive answer. But, in the past, I referred to it on the forums as a "water harmonic" because it sounded like it was in one place but the problem was elsewhere.

I was also informed of the need to replace the check valve at the hot water tank. One person even mentioned that they purchased a new check valve and then waited until the water quit running.

Heh....I'm procrastinator enough to follow that advice. Below is a picture of the valve I was told needed replaced. Sadly, it is at the top of the hot water heater instead of at the bottom. The difficult access is part of my reason for procrastinating.

Terry