After neglecting the Turbo Brush full of dog hair a few times, the Brush stopped spinning and would make annoying noises. Pretty much the Brush full of fur would jam, and the Brush motor would over-heat melting the plastic housing holding it in place. This would cause the tension in the Brush belt to loosen and weird annoying noises to be had.
To fix, you either have to remelt the plastic housing, OR, I have found that jamming a screw in the motor crevice will force enough tension again to grab the belt.