i have got a questiion about these tags. Well, I want to write a little program to be able to make customable mp3 lists. Due to that i need to know how to modify the mp3 tags. When i use my Texteditor to edit an mp3 i can see the ID3v1 (at the end) and the ID3v2 (at start) Tag, but if i modify them the file is broken. So, how can i do that? what is the key of editing these tags?