I'm restoring 2 RW's right now. 1 Buzzes loudly while one is somewhat quiet. They all have iron transformer cores made out of layers of sheet metal loosely stacked which means the fix on my website mentioned above won't work. There really is no way to completely quiet the buzz in layered cores. You can reduce it somewhat by restraining the layers better. I was able cut the noise roughly in half by pushing down with the tip of a screwdriver on the stack while inserting 2 layers of thin cardboard under each restraint. See photos.
stacked iron core
Thin cardboard inserted under each restraint
