MSI DVD Playback

I have started to get playback glitches( words , parts of video missing) on some of the DVDs I burn with a DR8-A DVD writer.It was made in Dec 03, ID DR8 AA03 12002106,
Model no DR8 A (MS 840 8A)
I burn DVDs, no more than 4 at a time using Grade A DVD s at 4x speed that have Ritek
Ink They are usually videos that I have processed with Coral Video Studio 11+ and burnt via its
buring module, these videos are one that I have filmed myself.I use a variable bit rate of 7000
and the video are less than 1 hour long(well below 4.3GB)
I have never updated the drive firmware and I think this may help the problem., but I cannot find
an update on the MSI website, are they still supported?
I have looked at http://global.msi.com.tw/index.php [...] =firmware+
which has some updates on it but I cannot find what I want(.XP HOME )
Can you help please
editman