You can see the same thing in all other modern (and not so modern) OS's.
Maybe when you are browsing the web, you can click on links in a distinctly timed interval, instead of at random? That way the OS can schedule it's response in a similar interval. Will 30 second intervals work?
If so, the mp3 you have playing in the background, will play a 5 second portion of the song, at 35 second intervals.
We can talk about where to schedule TCP sends/receives next, (and disk writes, and some other minor tasks)...
It's the nature of multitasking and priorities...
