The ID3 tag editor cited by SanDisk forum member Miikerman is “mp3tag”.
http://www.mp3tag.de/en/index.html
This free program for PC (shareware) has many exccellent features that are perfect for use with SanDisk players.
You can use it to quickly renumber audio file track numbers using 2-digit numbers with leading zeros.
ALSO, SanDisk players work best with ID3 tag data formatted as ID3v2.3 ISO-8859-1.
(I usually delete all other tag types, such as APE, etc)
