Not sure when I put it on shuffle, or why, but that was it. Didn’t even really realize that was a setting. All my other mp3 players just had a shuffle setting that you could turn on or off at any time… middle of a playlist, album, whatever. It wasn’t a secret setting like it is with iPods.
A side note for others, my car stereo has a USB port so I use a memory card as a hard drive. To get songs to play in a certain order I put numbers in front of the song name.