yup that was happening to me for a while because of permissions. First, make sure at least you have read/write permissions for the directory your mp3s are saved to. (get info on the folder, change privileges, apply to all within IF SITUATION ALLOWS - be careful with that) then after you're sure of that, it's always good to have iTunes convert and update all of the ID3 tags on your mp3s... you do this within iTunes.