I seem to recall having the same trouble when I first got my computer. I was using Adaptec CD Burner (which is absolute CRAP) and I was only ever able to fit about 8 songs on a CD. Needless to say this was tremendously frustrating. But I fiddled around with the burn options, and found that using "Track-at-once" is a better way to burn CDs than Disc-at-once, since if it screws up near the end, you can still close the disc and salvage whichever songs were already burned onto it.