Optiarc AD-7240S Problems burning on Verbatim DVD+RW media

I have an Optiarc AD-7240S writer.
I tried burning on a Verbatim 4x DVD+RW media using the Optiarc writer but it’s not working. I tried 2 discs but it still didn’t work, while on another burner (LG) it worked without a hitch.
I have no problem burning other types of media with the Optiarc writer (e.g. Verbatim 16x DVD-+R, Verbatim CD-R).
I updated the Optiarc writer with the latest firmware but it didn’t help.
Using DVD Identifier, I found out that the Verbatim DVD+RW media’s manufacturer is Mitsubishi Kagaku Media.
I’m starting to think maybe I’m better off replacing the Optiarc with an LG.
What do you think?
I thought that the Optiarc was a good writer (it was recommended on forums).
Your help would be appreciated.