BENQ DW1640 burn quality problems

I’ve recently bought a DW1640 and had much fun with it so far. Most burns with Verbatim 16x plus (DVD+R) media flawless with 99 Score in CD-Speed.
Recently I burned the last DVD of my first batch of Verbatim DVDs after not using the burner for some time (2 weeks or so) and there appeared some sort of a problem.

There are now always some PI failures around the 0.5 GB area. It’s not that they are really bad, quality score stays at 97 or 95 but what puzzles me is that the errors now always occur very near the 0.5 GB mark. I wonder if its the burner and if this may get worse. It’s also bad I can’t return the drive because it’s not a good reason to give it back because of some quality score.

are you burning with solidburn on for know media as i sugest that you deactivate this when burning quality media like verbs.

Its a common thing with some batches of Verbs. Mine had too. I guess just buy it from another place or use TYs instead. Even with those failures, a disc quality of 95 is a very good score. I have accepted it for my verbs.

I burned with solidburn enabled and disabled and the result is always better with solidburn enbabled.

This is somewhat comforting to know but still it’s a bit strange that the problem first occured with the last DVD of one batch and persisted on to the next batch. I guess I’ll try some other brands just for comparison. Not that I intend abandon my Verbatims. TY is the only superior brand and its not easy to get it here in Germany.