DONE employee, Tom Meyer, quickly found the reason for the toilet problem and did a total tank rebuild and thoroughly checked his work before he left. In trying to determine the cause of the "clunky" noise, he checked the efficacy of my pressure reduction valve by using a gauge at both exterior faucets. He said everything was OK with that. In checking at the front faucet, however, he found the overflow valve and the on/off handle suffering from old age. He accurately measured how to approach this replacement job from my basement ceiling, made a cutout and custom fit a new copper pipe from the existing pipe to the new exterior handle. It wasn't easy as the access was so limited by furnace ducts but perseverance and a minimal amount of assistance from me allowed him to successfully complete this project. Tom is a chatty fellow but professional, knowledgeable and obsessive about the details of his job. I'd have him return to my home in the future. As an aside, It turns out that the "clunky" noise was caused by the old shut-off valve to the toilet tank.