I’m curious, how many people are aware of these sounds. I have designed, etched, and built my own switching power supplies along with winding my own transformers. I am aware of the source of the noise. So, does anyone else hear these high frequency sounds regularly?
My main laptop is making similar noises all the time, I think they come from the CPU.
The CPU itself doesn’t produce sound, but inductors (coils) can. Therefore, when you move the mouse, the CPU power increases, potentially causing inductors to go into resonance.