In the past few weeks, our Kithchenaid dishwasher has made more noise than normal. Part of this is in the pipes when the dishwasher is filling, and some of it is localized within the dishwasher itself. There are no clogged drains, no foreign materials within the dishwasher compartment that I can find. I did do some work recently on the bathtub faucet that required turning off the water at the main and bleeding the pipes. Could air in the pipes be causing the problems?