I have never tried commercial cd polishing machines. I am not sure if they really help or not. As some others have said I think it would depend on how good or poor condition the CD was already in.
CD Repair?
I've seen several companies advertising CD repair by polishing out scratches. Here's a couple of examples: www.wefixcds.com & www.auraltech.com.
Has anyone had any CDs repaired? Successful? Worth the cost? Thanks!