All I can say is thank heavens for real experts who helped you fix it yourself.
I’d be interested to know if oxidation/dust on the potentiometer is the cause of this or maybe it’s just a bad component. I have had the background buzz (although not loss of sound) on some early Legacy/VL engines, including the Genset. It’s annoying and not least because it does not affect all of these models. Notably none of those engines was run shortly after they were issued; I bought them in sealed boxes a few years later.
