I have that kind of problem too!!!
And I don't know exactly what is problem!
Have you tried different cdrs? and what is your computers speed?
I'm not sure but I think that little bit make differense if you put your burner to slave or master!
but those "bad" cd what you and I get sometimes are mystery! because I think new 16-24 blank media can haldle 4x burner speed!
I still don't but all my copys work in my burner and my normal cd driver is allmost dead so that can't read even original?
You have to your "customers" what cdroms stose have! then you just have to burn with lover speed like 4... In worstes thing is when you have to burn 1x that TOO big time to wait!!!
So I don't have direct answer to your quesion!