if you suspect that the mediais to blame for a poor copy, just test it and try a diff media type. TDK has tarnished their reputation by lately using bad crappy Rytek dye. It was even in PC magazine here in the states. try any long strategy AZO dye or my personal favorite which is taiyo yuden (sony uses this, now so does fujifilm). This will help eliminate the idea that the media is bad which it can be possible. Also, at what speed did you copy these? Sometimes writing speed is a factor as well. Please let us know as much as possible.