This is an old story, but the first time I ever was in a real studio, back in 1975, I noticed a high frequency pitch. I asked what it was and nobody else could hear it. Finally we traced it down to the flyback transformer in the b&w monitor used for the front door camera. Nobody could believe that I could hear this with all the other stuff going on, but I surely could. I must admit that I earned a lot of Brownie points for this one. I was always plagued by this type of thing. I can't tell you how many times I walked into a control room and immediately noticed things that others weren't hearing. It was always hard for me to believe that other's couldn't hear these types of things which were so obvious to me.
