Annoying noise - automatic Octavia 1.4 TSI 2009

Hello everybody,

Before going to a service I thought it would be a good idea to ask around and hopefully, you guys could help me with this annoying situation.

When the car is idle a noise is coming from... somewhere  - I tried to locate it and as far as I can tell, it's coming from beneath the car, exactly under the engine. Another aspect is if you go in front of the car, the noise is fading, but near the driver's door, inside the car and if I go all the way down, there's "the best quality". As much as I can, I avoid it by putting loud music on but I still can hear it.  This is not always happening, but  7 out 10 stops, the noise is there.

Any idea what this could be? Please.

I recorded it and uploaded it to this website and to this topic as well.  

Thank you.

Memo 003_sd.mp3