Lol Guess why my screen is shaking

A couple of months ago I picked up a wicked sound system for my computer and right now I’ve got Three Days Grace cranked! The funny/ strange thing is that the window on my screen is shaking in rythm with the music. When I say shaking I mean SHAKING!

It’s at the point where its difficult to read. The window moves about a quater of an inch and the screen is waving in a cool kinda way. Anyone else ever had this happen?