Don't get it

I recently got an Mp3 player on the 16 of January. Its an Ilo. I read the manual and installed the programs. First few days it ran great, I got music on/off no problem.

But now, I can't get any music on. Bought a few songs, but I can't get it to stay. I sync them, the program SAYS they're on, but when I disconnect from my PC(windows xp) the music is not on my mp3 player. I can't sync it anymore because it reads as being on. Should I try to take them off and put them back on or what? Thanks for any help.