Cadillac 2011 DTS Owner's Manual page 264

When the CD contains only compressed files, the files
are located under the root folder. The next and previous
folder functions do not display on a CD that was
recorded without folders or playlists. When displaying
the name of the folder the radio displays ROOT.
When the CD contains only playlists and compressed
audio files, but no folders, all files are located under the
root folder. The folder down and the folder up buttons
search playlists (Px) first and then goes to the root
folder. When the radio displays the name of the folder
the radio displays ROOT.
Tracks recorded to the CD-R or CD-RW play in the
following order:
Play begins from the first track in the first playlist
and continues sequentially through all tracks in
each playlist. When the last track of the last playlist
has played, play continues from the first track of
the first playlist.
Playlists can be changed by pressing
the and
the knob, or the SEEK arrows.
4-102
folder buttons,
Play begins from the first track in the first folder
and continues sequentially through all tracks in
each folder. When the last track of the last folder
has played, play continues from the first track of
the first folder.
When play enters a new folder, the display does not
automatically show the new folder name unless the
folder mode has been chosen as the default display.
The new track name displays.
The song name that displays is the song name that
is contained in the ID3 tag. If the song name is not
present in the ID3 tag, then the radio displays the file
name without the extension (such as .mp3) as the
track name.
Track names longer than 32 characters or four pages
are shortened. Parts of words on the last page of text
and the extension of the filename does not display.