Its a very distinct whining noise, I mistook it for wheelnoise.
Drove our X3 from Norway down to Italy and back, last summer. On the way back, halfway through Germany I started hearing the noise. Took the car to my nearest dealer (Hamar Bil) when I got home, the front left bearring was finished! They didn't have the parts in stock, so I called the dealer where i bought the car (Autozentrum, Oslo). The X3 had only done 40000 km at the time, so after a short discussion they replaced it free of charge