squeaking sounds from the front wheel at low speed, not braking

[ak11214]

Hi all,

I have an audi a4 2011 awd P+ with 26k. Recently there is a low squeaking like sound (like metal rubbing against metal) coming from the front wheels (not sure which side) at low speed 5-15mph. I can hear it with the windows open. It happens at low speed (accelerating) and/or cruising with gas pedal not pressed. The sound stops when I press the brake. Any idea what could be the problem? I googled this and some said it might be grit stuck behind the dust guard. I would love to hear everyone opinion.

Car is 100% stock, I believe the brake and rotor are original. Also when I had the car inspected at 24k, the brake and rotor are in excellent condition with plenty of life.

Thank you all.

update:

So I took a video with the squeaking sounds. I apologize for the wind noise, but you can hear it clearly at 0:50-0:59. Thank you all in advance.

https://www.youtube.com/watch?v=bSplKHc_YfM

What could this squeaking noise be coming from?
-Rusty rotors
-U joints
-other suggestion?