I have a digital music changer that simulates a cd changer for my car radio. It can read mp3 files from an SD card, however the order of playback is determined "by time the file was copied to the SD card".
I made the following observations:
- Copying multiple files at once (tested only via drag & drop) leads to almost random playback order
- copying file by file by drag & drop leads to a random playback order that (not verified) seems to be equal to to playing order when copying all files at once.
- copying file by file using the clipboard shortcuts leads to correct playback order.
I also wrote a simple C# program to overwrite the create / accessed / last write time properties of each file in alphabetical order, however it had no effect on playback order. I changed it to copy each file one by one, which didn't help either. Using a program called "Mp3DirSorter" also didn't help.
My current guess is that the device reads files from the FAT32 file table. If this is correct I wonder:
- Why does drag & drop and Copy-Paste lead do different results?
- How can the files be rearranged in the Fat File Table? (possible duplicate question)
Addition: it might be worth noting that the SD card may not have been formatted between each test.