I have a ND-1300A (running on XP) and it started out working fine, then it simply died. I can still burn CDs but I can get it to burn DVD anymore. I'm using NERO and when I try to copy a DVD it blanks out the write DiskAtOnce option box. I get similar messages when I try to burn a DVD with other software, and with different disk brands (and speeds). I thought something might have monkeyed about with my ASPI settings to I tried to replace them and now as far as I can tell they're OK but my DVD burning days seem to be over. Any ideas are welcomed!!!
If you're running XP, you might want to try and use the Restore feature to a date when your burner was still working. If that doesn't seem to work, then you can try reinstalling Nero, and worse case scenario, reinstalling everything from scratch.