I was just at the dealership, mechanic told me that it is a normal noise, it is the sound of air intake. It is only noticeable before 3rd gear engaged. hissing sound. He said it was louder with Gallardos, they constantly had owners coming in for such problems before. I used to own a R8, it did not produce such noise at all, Mechanic said: Lambor uses different air intake system than the R8's. No worries! enjoy the hissing sssshhhhhh!