Rattling noise coming fro engine bay

When I start my car up from a cold start it is fine and runs smoothly with no rattling, but after a short amount of time roughly 10 mins, a slightly rattling noise is created from the front and is very rapid and loud when, accelerating at 3000 revs and or going up steap hills, but is not always consistent to the revs, anywhere above 2000 and it generally makes the rattling noise very loud and rapid, also sometimes when idle it is still there but is faint and a lot calmer. The rattle is quite high pitched and loud enough to here over music when accelerating