There are two ways that iTunes can be used to delete songs or playlists from your iPod; automatically and manually. The method you use depends on the preferences you chose in iTunes.
Notes 1. If your iTunes Library contains more than 1,500 playlists, some playlists will not be displayed when setting your iPod to sync only certain playlists.
more information :
http://www.softwarebbs.com/wiki/Automatically_adding_and_removing_songs_and_playlists - written 3 years, 4 months ago
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