Rattle sound on cold start
 

My issue is after i start the car and let it idle down to the normal rpm i start to hear a rattle hard to say where it is you can here it alot in the cabin. After i drive the vehicle for even 5secs the rattle sound goes away. Any idea what this may be be from? Sounds like possible engine bay or exhaust but cant tell for sure. My dealer just replaced my throw out bearing and afterward it has gotten alot louder.