a usb drive is just a storage device. a computer can read data from it, but it can't play music on its own. you need something in between that can play music
>>105923086 (OP)
Buy a head unit that doesn't fucking suck.
$300 pioneer unit for wired or wireless carplay and android auto.
Yeah you can plug in an AUX cable if you're autistic but you may as well use the DAC/AMP built into the fucking car
the only way that would work is if it was an ipod shuffle style headphone jack where it's also a usb port. if op isn't just kidding, i can only assume he got the idea from that.
a regular "aux" port can't do that, it's not a standard feature