Vibrating and humming noise in pipe

[Pinkcandy]

Hi, this is my first post. I would be grateful for your advice.

This has been happening intermittently, usually when hot water has not been used for a number of hours. When I turn on the hot water taps, I can hear a humming noise and the pipe linking to the kitchen hot tap vibrates.
To stop the vibrating and humming noise I have to turn on the kitchen hot tap for a few seconds, otherwise the vibrating and humming noise would continue until I run the kitchen hot tap. This only happens with the hot water taps and not the cold taps, shower or central heating.

Plumber has been and because the vibrating and humming noise is intermittent, he couldn't hear nor see the vibrating pipe. So problem is still not fixed. Please help.

 

[Pinkcandy]

Any plumbers here? Have already paid £40 for a plumber who could not fix the problem. All he did was to tighten the kitchen tap and changed the bathroom sink tap washers.

 

[denso13]

Any plumbers here?

Loads

 

[GavThePlumber]

Have you got a cold water tank in your loft?

 

[Pinkcandy]

Yes, cold water tank in loft.

 

[Nige F]

£40 for a plumber in London is good . Maybe we should do like solicitors , no fix no fee BUT £400 an hour like them