Earlier today I burned a DVD and immediately took a scan. Scan 1 shows some very pretty results. Then I watched the program on a stand alone DVD player and then ran another scan. Scan 2 is of the same DVD several hours later.
I have noticed this before with other DVDs. Is my stand alone DVD player destroying my disks ? does this happen to anyone else ? and does it matter ?
The transfer rate tests still show rock solid results and there is no difficulty playing or copying from the DVD.
Hmm… Odd… Make a third scan… just to be sure…
done again + transfer follows.
First scan PIF max 4
Second scan PIF max 10
Third scan PIF max 11
All three PIEs are still excellent.
How about watching it again (fastforward) and scan for the 4th time? 
Very interesting…
Why is the last REGULAR speed test start at about X3 and not at about X6 ?
You did not say what system you have, ie, external, interface, Operating System, memory, etc. Also please use in this test the CPU Usage and burst rate, might give some clues. Also, must have very quiet system with no other work to evaluate the results.
The write speed line (green) is smooth so no problem with his system.
I’ve seen this happen when a bit of dust gets onto the disc surface.
Cleaning the disc fixed the scan.