Prentke Romich Company
http://www.prentrom.com/support/article/1587
MP3 Player Menu 

WARNING: PRC reminds you that music files fall under the jurisdiction of all copyright laws.
In order to play music files on your device, you must have songs stored on a USB flash drive a Secure Digital card or the internal hard drive if you have that option.
Tip: While music is playing, you may use your device as you normally would.
NOTE: If your device has an internal computer, you may also use Windows© Media Player to listen to music.
OFF
No songs will repeat.
All
An entire playlist, or all the songs on a flash drive, will repeat.
1
This repeats the song that is currently playing. The song will repeat until you select Stop, Next or Previous.
Your device will play songs that you have currently selected. Unless you press Stop, music will continue to play until all the songs on the playlist have been played.
You can pause a song by pressing Play while the song is playing.
Select this to stop listening to music.
This option allows you to create one or more playlists. It will also play any playlist that is selected.
Select Previous to listen to the song before the one currently playing.
Select Next to listen to the song that follows the one currently playing.
If you turn this ON, your device will play the songs on your playlist in a totally random order.
This option controls what happens when you want to speak while a song is playing.
The music pauses while you speak. When you stop speaking the music resumes.
The music stops. To listen to it you must select Play in the MP3 MENU. The music will start at the beginning.
The music will continue to play while you speak. Off means "No speech break."
Turn this option ON if you have earphones plugged into the device.
This equalizes the volume level between different sound files. It also lowers the sound volume when you want to speak while music is playing. This option is independent of your device's speech volume control.
Customize the bass sound level.
Customize the treble sound levels.
Select Playlist to Play
Search for playlists on your hard drive, USB drive or SD card.
Search folders on your hard drive, USB or SD card for songs
Select files from your hard drive, USB or SD card for songs to play.
These options allow you to search for and select any songs you have saved on removable media (USB or flash card drives) you have plugged into your device or have stored on the hard drive.