Its not the mp3s if you can listen to them on your computer, its more than likely the brand of disc your using, some brands like certain players, I was advised this from a sales person at a computer store, I use Imation and they play in all my stereos and I just purchased the brand Verbatim and have had no problem with them......
What program do you use to burn the music, it could be the way your setting that up as well???