Hi everyone I’m a newbie 😊. I’m a landlord and one of my tenants has been complaining about an intermittent noise which I think may be coming from a neighbour upstairs but I’m not sure...does anyone recognise what might be causing the noise? It sounds like pipes banging and happens at random times of day when my tenant is eg watching tv and hasn’t touched the taps all day. Also heating is off at the moment and we have a 3 yr old vaillant combi boiler in another area of flat so can’t see it’s that. Any help would be so appreciated! Thanks in advance.