Probably not what you want to hear right now Ed, but if it’s a pipe leaking you’re better off sorting it out sooner rather than later.
We got a message from Affinity Water saying our bill had gone up significantly due to a massive increase in use over 6 months. We found a pipe was leaking (thankfully under the house) but it was literally pissing out water like a tap.
Thing us we could hear it at different times of the day but I assumed it was our water softener unit purging. We got the excess bills written off and were lucky it had happened under the house where it was doing no damage. Repairing walls / floorboards / ceilings and redecorating due to a leaking pipe left unchecked will end up a massive cost - not to mention absolute ball-ache to resolve