hhmm..the PAD had a crack? Did the metal plate have a crack too?

You might need to have someone help you out with testing that out. If the noise persists. Put the front up on jack stands. Then turn the car on and ask the person to slightly accelerate(with both front wheels off)...and then brake....see if you can pin point the sound. Its a more hard way of doing it, but you can HEAR where its coming from!

Dave