My car audio system has only a USB Memory input (it does not have Bluetooth). The audio system is able to read the content of the USB memory, find the folders (MP3 files) and show them on the screen.
I was thinking to use a Raspberry Pi Zero W to setup it as both a Bluetooth Audio receiver and USB Mass Storage. Then write a program to write the Bluetooth audio as an MP3 file into the mass storage space, and keep updating the MP3 file in the hope of the audio system of my car be able to open that MP3 file, show the metadata on the screen and play the MP3 audio.
Is such solution even possible with Raspberry Pi Zero W?