Things You'll Need
Instructions
Disconnect all cables from your Xbox 360 and power the system down.
Turn your Xbox 360 around so that you can see its rear panel. The vents that reveal the inside of the unit are on the back.
Hold the nozzle of a can of compressed air a few inches away from the back of your Xbox 360. Pull the trigger on the can and spray out all visible dust that is covering the vents on the unit. This will clear off the dust on the vents, the dust on the internal fan (just on the other side of the vents) and any dust on the inside of the unit as well. When you turn on your Xbox 360 again, the buzzing noise will be greatly reduced.