Hi

Every time I step on brakes I hear pretty loud mettalic clanking noise from the rear of the car. It only happens after I drive for a while. when i'm parked i can be pushing brakes and nothing happens, but when I drive - it happens every time, but only the first time i push it... if i "pump" the brake pedal few times - i get the noise only the first time. It's been going on for a while. I had calipers,discs, pads replaced a month ago - the noise stopped... it came back few days ago..
Any ideas?