Corsa-B.uk - Vauxhall, Opel and Holden Corsa B Owners Club

I dunno if anyone can help me, my corsa has a high pitched rattle but it isn't consistant. Sometimes it rattles until you reach a certain rev, sometimes it stops rattling when you drop the clutch and sometimes it just constantly rattles. I thought it was the gear box but i had it checked and it wasn't that, then i was told it's the exhaust by i had that changed and it wasn't that, and then i was told it was my break pads rubbing so i got new breaks and pads and that hasn't solved it either. Has anyone else had this problem?

there could be something loose in the engine bay?