Hissing noise

[S23]

Started up and but on the front window demister after the wi Dow cleared I drove up the hill and a loud hissing was coming from the glovebox area
anyone else had this ?

Also whenever I turn the car off is makes a hissing from outside under the bonnet ?
Is this just any pressure in the turbo being relesed ?
Thanks

 

[swarcup]

the outside hissing is the aircon system and is normal, they all do it. The inside maybe a pipe that has come adrift, take the glovebox off and have a look.