Did you test the Ritek GO4 in a dvd-rom drive or your burner.
Did yo use cdspeed 210 free from ahead (nero) software to test the burned media.
What firmware is on yoiur burner.
I`m sorry I have to ask these questions but many of us who own a NEC 2500A have serious problems with Ritek Media.
Any other DVD brand I have used burns perfectly with the NEC 2500A.
In my experience with the NEC it points to the Ritek media.
Any help would be appreciated.
Thanks in advance.