We replaced the copper pipes in our home due to pinhole leaks. Now, they are making noise, almost like a loud dripping noise hitting the floor. They are not leaking but they sound like a constanct "crack, crack, crack" as the water runs down from the 2nd floor. It is driving me crazy! What can we do?

Hmmm... you may have actually overhung those new pipes... or pipes are rubbing up against the wood. Go downstairs and see if can loosen a hanger... that may help.