Hi all. Im trying to help a friend of mine in school. He is a drama teacher, trying to organize amusical for the fall semester. He has received cd's from his usual source, paid the fees to have copies made,and all the copies he made have some popping sound in all the tracks. I tried his original and found that his "original" was also a copy, albeit a very good copy. I have tried the usual detection programs, clonyxxl, cd inquery, cd-info, etc. Can anyone offer a suggestion as to how I can discover the protection used on the cd? Thx.