The old shop I worked at had some sort of spray for quieting noisy yokes. Would penetrate the windings and dry. Probably not much more than a clear coat with an enamel-safe solvent.
OR listen to enough loud music and go to lots of concerts over a 20 year period with no ear protection, give yourself tinnitus, and that 15,734 Hz horiz sweep noise will be drowned out by the internal ringing in your head! I know all about that, Used to be able to hear up to 22k....
EDIT: Looks like one brand of that spray was GC Electronics #10-8665.