[Three_thirty_I]

That sounds like the brakes, this noise is common on various E9x models, my 330i has done this from time to time since I've owned the car, and lots of 335i owners have the same issue. What makes it seem strange is that it makes this noise when you are simply moving along at those lower speeds without touching the brakes, and you will most likely have noticed that the sound goes away when you actually apply the brakes. And to be honest, I am not even sure if there is a proper way to solve this, some say it's the dust shield, the brake wear sensor is not really what I think is causing this since that is only on the front left and right rear. I wouldn't stress about it, even if it is a tad annoying, it's a quirk as far as I am concerned.

Edit: so, spams the forum with 6 identical threads, gets a reply, doesn't bother to acknowledge it or reply...