K, i just redid my bathroom, I did not have to do much plaumbing work except I did redo the valve for the shower. I went from the standard two valves to the newer single valve. No other plumbing was changed. Now that i have thebathroom finished and done with, every time water is turned on and then off in the house, you can hear and wierd "growl" coming from the walls throughout the house. Growl is not the right word, but I cant really think how to describe it. Almost as if the pipes were beingput under a tremendous strain or something. Was wondering if anyone had any ideas to what it may be and then agin, how to fix it!!!!!