Im using Nero 6 Enterprise Edition, and when I use a "Smartbuy" DVD-R 8x i receive an error "Focus or tracking error". No DVDs I've tried work. CD-Rs are fine burning, reading DVD-/+R is fine, but burning is an issue. The firmware is a203. Should I upgrade to a207? Would I notice an improvement? Should I try another form of media like verbatim or Dvd+r?