When my Yeti is sitting ticking over there is a sort of pulsing, hissing sound, anybody explain this, or have the same issue.

Could it be the fuel pump.  I have much the same car and I think my fuel pump is on the way out.

Any loss of power when driving? If so could be a turbo leak.

Thanks for the replies, no loss of power but something that just makes you question " is there something wrong"

Going to ask my mate who is a VAG Specialist.

Could it be a leak on the vacuum pump?

 

open the bonnet and listen - try spraying a little WD40 around any clips holding "whatever" - does the sound go away or change 

Might be way off but does it come and go with the A/C? When my air-con needed a service I noticed a hiss