This is the first time I've noticed this thread (I see it was brought back because of a spam post
) but I wanted to add my .02 cents. I get this same kind of buzzing with one of my HAs. It is the analog HA that does that (and not the other, which is digital). It happens only when near things like microwaves, a radio, etc., and not all of them, so only some makes/models of appliances cause this. I guess based on the radio frequency.