But why does the squeak happen? The metal rotor that the brake pads squeeze together can sometimes vibrate, causing a squeaking noise. Luckily, there are several ways to fix this:

•Use a milk spray, lotion or cream on the back of the pads [source: Allen].
•Use sandpaper to sand off surface hardening of the brake pad/shoe surface.
•Try a different brand of brake pad!

Link http://auto.howstuffworks.com/auto-p...-squeaking.htm

or you can try shave your disc. cost 10 bucks a disc at meekong. but check if your rotor can be legally shaved or else get new ones. and make sure you grease the back of your brake pads. use high temp grease.

or you can just crank your music up... problem solved lol