BeezySBaby

Hey all, I've had my A4 now for about 2 months, and have noticed a weird sound a handful of times when shutting the car off. It almost sounds like a vacuum closing, or vents shutting, but I can only describe it as a very brief "sucking" or "burping" sound once I put the car in park & press the On/Off Button. There is just one little "burp", during the shutoff, and that's it. Nothing weird on the next startup, no "whooshing" sounds like coolant (believe me, it's the first thing I thought too), etc.

Thing is, I cannot ever replicate this under any circumstances, and it has only happened a couple of times, so I'm not sure that it's even out of the ordinary. I have not taken it in or anything, and the car has been working flawlessly, both mechanically and electrically, so I just wanted to get some opinions on what it could be? Any thoughts as to what systems could be shutting down to make that sound?

VipinLJ