1GB Express and not playing all mp3 on player or external disk


I would like to know if anybody else is running into the issue of the express 1gb not playing all songs when selecting to play all songs?

I updated to the newest firmware flawlessly, and have converted all music to mp3 format. I have 111 songs on the player, and everyday, I seem to hear new songs, ones I thought I heard since I went through the whole list within four to five hours.

Any ideas?