about a month ago our pipes started humming when the water was turned off in the shower. Then it started doing it when one fo the toilets was flushed. Now its doing it when the cloths washer is on. I've also noticed in the last few days our water pressuer is not like it used to be. when the humming starts i can open an faucet and it tops right away? would draining the water pipes and refilling them help? would anything else help?
thanks