Strange noise when changing gear

Doogle

Winner - POTM March 2018
Hey Ladies and Gents,

I am trying to identify a weird noise, it sort of sounds like a slight hissing/whistling sound. Its not overly noisy, only happens at low revs or when changing gear (letting off accelerator at low revs) I was wondering if it may be an exhaust leak? It appears to be closer to underneath the car instead of in the bay itself but its hard to tell.

Doug