I have a Raspberry Pi 2 running Open Source Media Center (aka OSMC), and when it runs, I hear a very high frequency hissing noise coming from the Pi.
In my family, I am the only one able to hear this (as well as the one able to hear some noise from the dimmer of my desk lamp), but it's extremely annoying, mostly because the Pi is located in my room and this forces me to turn it off when I go to sleep.
Another thing I have noticed is that a Raspberry Pi 3, which I have also been using lately, does not produce that awful sound. Is this normal? What can I do about this? Or is my Pi just broken?