E53 3.0i whine

[GaryC]

Good afternoon. I have a 2004 E53 3.0i and I have a whistle noise inside the cabin that is driving me mad.

I have a brand new induction boot and a new DISA valve.

Oddly, you cannot hear the whistle in the engine bay with bonnet open, but sit in the car with radio off, heaters off etc and rev it and you can hear it. It goes up and down with the rpm of the engine.

here is a video https://www.dropbox.com/s/skw3e6wk8o..._4581.MOV?dl=0

Any ideas? Thanks in advance!