Weird noise coming from 2017 X3

[Ann9787]

I just purchased a 2017 X3 about a month ago and in the last few days have noticed a strange noise coming from the left rear passenger side. It is noticeable only at slow speeds like when I am driving through my subdivision and especially when I am driving down a hill. I can only describe it as a low, hollow sound. At first, I thought it was something I had in the back just vibrating but I removed everything and it is still noticeable. I am not sure where to take it or where to start. Any ideas on what to check for? Thanks.

[MarcoZandrini]

Have someone sit in the back seat on the left side and use a smartphone to record the sound. Then upload to a file sharing website. Post the link.

[shogun]

Moved to X3 forum