Nah, they're definitely using tags. I tested this out by tagging an audio file with the name of each tag, i.e. Artist=Artist, Title=Title, Album=Album, Album Artist=Album Artist etc. This way when I play the file in each vehicle, I could see exactly which tags it was using. All of them were using the Artist, Title and Album tags from the AAC file being played on an iPod via Bluetooth. I didn't do any testing via SD Card or anything like that as I find the way that type of interface is used to be very unintuitive.
No difference with MP3. They all still read Artist, Title and Album tags, just as they did for AAC.
Yeah, I thought about installing a different music app to use, but considering the increased storage space requirements I'd need and seeing as how the bitrate of the Bluetooth codec that an iPod supports is nowhere near my FLAC files, I didn't even bother.
