Both back wheels make a clicking sound - 99 Grand Am

My breaks work perfectly. My car has a clicking sound when driving. I jacked up the car and spun the back tire and it makes a clicking and clunking sound every time it goes around. I jacked up the other side and the other back tire also makes this sound. It seams really wierd that both tires make this sound. It seams very load when spinning the tires, my friends could hear it on my phone about a yard away from the wheel. I have drums in the back and the sound seems to be coming from inside of them.