I can't see this being a real problem. If by some fluke somebody got hold of the CD and started giving it a lot of airplay and you started racking up sales - that would be a different story. But then you could probably contact the parties involved and come to some kind of arrangement. However, if you are sending the CD out to be duplicated (versus burning it yourself on your home computer, for example) they will require you to certify that you have taken care of all copyright obligations and legalities.