Anyone have anything on a VW UP engine rattle at 2500rpm?

I’m guessing it’s a resonance frequency causing a rattle in a piece of engine bay heat shield tin.

But has anyone come up with a fix, eg adding grommets or some sort of off the shelf engine sound proofing membrane/ fabric?

I’m also guessing it is from something near the gear box as it won’t make the rattle if in neutral and rev’d through 2500 rpm but it will rattle if in gear at 2500 rpm.

Cheers
James