Studio Display High-frequency Noise

[Kim Kyoung Seop]

My 2 years old Apple Studio Display 15" LCD makes annoying high-pitched 
noise.

I'm not talking about the buzz coming whenever you decrease the 
brightness. I'm talking about the noise always on, very very 
high-pitched sound. It started last week and stops only when sleep or 
shut down.
Weird thing is my wife barely hear it! She is not so deaf or dull.

I've heard some capacitors of a display make such noise and you should 
have it repaired. But my studio display is out of warranty.

How can I eliminate the noise?