USB MicroSD card reader for music?

[Offroad]

Does anyone know if it's possible to plug in a USB MicroSD card reader into one of the USB slots in order to play music through the car rather than uploading music to my phone and playing it through Android Auto?

 

[youri]

I have not tested it but in theory that should work. The car will see it as a regular USB stick.

 

[Odrapnew]

I don't have a CX9, but I have a USB microSD adapter with a 16gb micro SD for my music and it works fine.
As youri said, it just sees it as a USB, should work on the CX9 as well.
It was something like $10 from Amazon.