I have a reasonably loud Electrical buzzing about 10 minutes after
warm up on my Carver M500t which I suppose is a bit elderly by now.

Sorry if this sounds a bit unsepcific but does anyone know what can
cause that type of thing please? Do these things suffer from anything
as simple as leaky caps or is the unit probably terminal.

(I should add that I am in New York where there is unlikely to be
anyone nearby who can fix it so if it is not easy, I amy well not be
able to do it myself)