As mentioned our pipes are humming since having a water meter fitted. The water board sent a man round. He couldn’t fix it. He said he’s not a proper plumber and they would need one to come out. So sorted that and just had the call that they would be here in 15 minutes, However it turns out it is exactly the same guy coming round. Hooray! This has only been going on for several weeks.
No need to post in here but I thought you would want to know.