The problem is that when mp3tofid changes the fid number of a tune for whatever reason, it does so on the PC, not on the player. When you sync the tunes to the player using rsync, there's nothing there that can tell you which fid numbers changed to what.

One approach to this problem would be to have mp3tofid create a log file, containing all fid numbers of new or changed fids. This way, an application on the player could read this file and only reset the data for these fid numbers, leaving data for unchanged fids intact.

Pim