I have a mystery sound as well. I've captured it on video. It only happens when I start moving. Never notice it at high speed. Happens driving straight or turning. Listen at second 10-12 and 28-34 of video. Thanks.
You tube video: https://youtu.be/Rc4Al5Qrj9s
You tube video: https://youtu.be/Rc4Al5Qrj9s