I am repeatedly seeing, with several different USB devices, the car lose album/artist (but not song) tag information after a day or two. My current in-car collection has 124 artists, 239 albums, and 2,737 songs. The first time a renamed or reorganized usb device is inserted, everything is scanned correctly within a couple of minutes. But then a day or two later, the car has lost tag information for more than half of the artists and albums, but still has all of the songs. The folder view also remains consistent. Replugging the USB device does not force a full rescan. Rebooting the console and replugging the USB device, also does not cause a full rescan. The only thing that seems to force it to refind everything is to rewrite the device with some combination of relabeling the device and/or reorganizing the layout (typically renaming the top level folder).
Setup:
Filesystem: seen with both fat32 and ext4.
FS organization: top_level_folder/{artist}/{album}/{mp3s}
Tag generation, done with Linux. Note, in an effort to establish a working baseline, I am not even attempting to handle compilation albums:
Create copy of the original mp3 files.
Sanitize all artist folder names (replace diacriticals, spaces, punctuation)
Sanitize all album folder names (replace diacriticals, spaces, punctuation)
Sanitize track names (replace diacriticals, spaces, punctuation, add/normalize leading track numbers 01-track_name.mp3, etc...)
Extract artwork from each track and convert to 300x300 jpeg.
Clear all tags on all tracks.
Set the following tags:
Artist (TPE1) - to the name of the artist folder
Album Artist (TPE2) - to the name of the artist folder
Album (TALB) - the name of the album folder
Title (TIT2) - the name of the track
Track (TRCK) - the leading two digits of the track name (01, 02, ... 17, etc)
Image (APIC) - the 300x300 jpeg
Set full access permissions on all folders and files (0777).
BTW, here is a handy site showing the tag name mappings for different tools/platforms:
http://help.mp3tag.de/main_tags.html
I suppose that my next step will be to binary search downward in collection size to see if this misbehavior is size based.
Any suggestions? Thank you.