I have a handheld shower head. When I turn on the hot water in the shower, the hose bounces in the holder, and the pipes make a thumping sound. This only happens with the shower faucet- not with the tub faucet or any other faucet in the house. It also only happens when the dial is turned to hot. (There's one dial in the center above the tub faucet that you turn from cold to warm to hot. It also has a temperature monitor to protect against scalding.) I thought it might be the diverter in the tub faucet- the thing you pull up to by-pass the tub faucet and send the water up to the shower- because it was leaking water out of the faucet while in shower mode. I replaced the faucet, so it no longer leaks when in shower mode. I also opened all known water valves to full. That made it better, but it hasn't stopped. Also, the shower pipe can be moved in and out of the wall- like when you put the shower head back up to the holder. Could it just be my handheld needing to be replaced- like it's in vibrating mode permanently or something? Or that the pipe's not secure in the wall? Help! I'm clueless. I know I probably have hammer thingy, too, because the toilet makes a thump when it finishes filling- although that's not as loud anymore either. What to do?