Strange noise in Audi A3 3.2 Quattro MY2005
 

Hi guys,
I have discovered strange noise coming from the engine. The engine is running fine and no error codes appear on diagnostic.

I would really appreciate, if someone had any idea, what the noise is. You can hear the noise on the following video in 5th and 47th second.


It sounds like something is blowing some air away, but I'm not sure, if it's OK, or if I should worry about it. It makes this blowing noise only, when the engine is warm, so no noises on cold engine.
I was at my Audi local service and from listening they said, it can be the change-over barrel in the intake manifold, but the engine is idling and the change-over barrel is turning 90 degrees only, when the engine reaches 3950 RPM, so while in idle, the barrel shouldn't move at all, so I don't think the noise can come from this barrel.

They offered me to check the car, take out the engine and we'll see, if they find something, but only the engine removal is expensive.

Thanks a lot for any ideas, what the noise could be.
Tom