812s (US0N) errors out burning @ 4x on -R...(long error code/message inside)

well, i have a Sony DW-U18A with US0N firmware, omnipatched with only automatic bitsetting.
Burning DVD+R verbatim datalife plus at 2,4X i have no problems, but burning DVD-R verbatim or Akira at 2x shows me an error writing lead-in…
I don´t know what to do with this problem…
anyone know how to get correct burns with both media (+R & -R)?
DVD-RW & DVD+RW verbatim works fine to me.

I have good results on burning Ritek X4 DVD-Rs after getting my new 812S using US0N update. The following is the scan. See my other post in this thread http://club.cdfreaks.com/showthread.php?t=101363