Car Squealing Noise when cruising at low speed. Cause?

[Ferra]

Just starting to notice that my car is having this tiny squealing noise when it is cruising (or lightly accelerating) at low speed (<45km)
It sounds kinda like squealing brake except much quieter (Can't hear it with the radio on), and it will completely disappear when you apply the brake. You only get it when you are cruising or lightly accelerating or decelerating .

What is causing it?
Car is an 06 330i, still under warranty but it is very inconvenient for me to bring the car in, and I am returning it in a few months(end of lease). So if it is nothing serious, I will just leave it the way it is.

[shenmecar]

perhaps a belt? my belt makes chirping noises at low speeds.

[JesseBlue]

i think its the brake...i'm having the same issue right now..

[achiam]

There's a huge sewer rat caught in your fan belt.

[Lomac]

One of the pads may not be coming back all the way when the piston retracts. Or it's possible your e-brake line may need to be adjusted.

[buddy]

i think you will have better luck posting questions about your 330i in Euro Tech than in Honda/Acura Tech ...

[nickmak]

might be a belt? BMW's don't have squeelers, so low brake pad lining isn't the cause!