Svm, in my experience with burning, then doing Disc Quality scans on Cd-DVD Speed or Plextools, I never saw any difference (more or less errors) when I used bitsetting to change my +R media to be recognized as a DVD-ROM when burned. It’s possible your ‘phenomenon’ is just the variable quality of MCC004. Sometimes you can have the top 50% burn well and the bottom 50% in a spindle burn below your normal results. I’ve seen ppl burn one DVD blank well, with the next burning like crap in comparison, but then all the blank medias after it were fine. There’s no way to say for sure, unless you turn the DVD over to the dye side and examine it under a light. If you see some lint, dust, or dye splotches, then those things could have caused the PIF spikes also. I’ve examined my DVD medias meticulously and sometimes found nothing to show why I had a huge PIF spike in one spot (no dust, lint, dye spotting, etc.), but when I rescanned it, it was still there. Even when the media appears defect-free to the eye, there could be something there causing the problem.