I don't always run the water for a while at first. So we do have air but it seems that there is loud crackling that is more than air. No such noise at the kitchen. (This is our fifth year using Escapes and we have used them a lot more than most people, out this time since mid March.) We also had the leaking shower, too, but seems to be fixed now. Have not really cleaned out the hot water tank well but have one of those little hose attachments to do so next time. The bath plumbing or sink is obviously not the same as in the kitchen and we are getting very different noises!