Not sure if its the same problem or not, but I just had this same noise. It was a slightly bent backing plate. Had my friends over at Tire Discounters check it out while I was having my tires rotated.
Take a screw driver and tap on the backing plate, you'll recognize the sound right away.
Mine wasnt that bad and the noise only showed itself when I took a hard right turn with alot of downward force on the front left wheel.