My macbook air makes robotic sounds.

On random occasions, such as when I'm watching a youtube video, my macbook air would make a warped robotic sound. The volume doesn't affect it and it only goes away if I refresh the page. What is happening to my laptop?! My macbook air is not even a month old, the newest 13in edition. I noticed this the first time I turned it on and watched my first video. This happens infrequently, but often enough for me to wonder what is going on.