Why can I hear the cursor flashing on my screen through my headphones?

Question

As well as just about everything else that changes on the screen, from loading a webpage, scrolling a window, typing, moving the mouse around, etc.? I have the headphones on, and I can hear it all. When I try to record a screencast with Camtasia 7, I get a lot of noise in the audio track.

I have an Asus desktop (within a year old). 64-bit running Windows 7.

Thanks for any suggestions! If I need to provide more information, please let me know.

Edit: The noise is like a high-frequency whirr with different high-frequency chirps when the different activities on the screen take place. They're not loud chirps, but I can hear the frequency of the whirr change a bit, if that make sense.

I have a wireless keyboard and mouse. Someone else suggested switching those out with a wired KB/mouse.

Answer 1

It's called Electromagnetic Interference. It's very common with electronic devices, and is usually most noticeable by speakers or headphones, as you have noticed, but can also be picked up by radios, TVs, telephones, or any number of other devices.

You may be able to reduce or eliminate the problem to get a higher quality of headphones--specifically "shielded" head phones. It might also help to use shielded cables for your other electronic devices--like your monitor cable, etc.