air escaping when turning engine off - normal?

[shod]

I always hear this err... farting noise... from the LR3 when walking away from it in my driveway. its sort of a short **** of air escaping some reservoir (sometime happens twice)... is this an air suspension thing that I should learn to ignore?

 

[grommet]

Self leveling air suspension. Sure it's been covered numerous times...

 

[Insider]

Normal, Yes.