buzzing

So I have a stock 2010 Mazda 3 and I'm having some speaker buzz problems. At first I thought it was just a blown speaker but sometimes the sound sounds 100% clear and other times it is all garbled. I think it might have something to do with the windows, maybe a short somewhere or something. More...

Part one: So when I'm driving along, it sounds like both my front tires are wobbling in the ends of their axle. My alignment is spot on, though, and the steering is tight. That noise just makes me nervous. Does anyone know what's probably causing it, or a simple/cheap way to find out? If you...