Re: need helping with humming on blue yeti pro.

[Matthew Bullis]

When I had a similar problem with the turntable rumbling back into the 
nearby speakers, I had to put a piece of foam on each of the four feet of 
the turntable. The foam was the same type that you find in a foam matress. 
The pieces were at least an inch thick and not solid foam, but spongy foam.
Matthew