Here’s a wierd one.
Im running Win XP Pro SP1A, Nero 6, and DVD Shrink 3.2
I’ve been using Mirror 4x DVD-R’s for the past 6 months on my Sony DRU-510A with no problems, then just the other morning it stopped recognising them. It would still write to CDRs and DVD+Rs, and would read all formats. Nero just kept trying to initialise the drive, then said the media could be defective so I tried 5 different discs with no success. I then tried a +R and it wrote straight away.