NEC 3520A plays DVD+DL, Explorer won't read it though

[autotran]

I copied my Apocalypse Now Redux DVD on to a RiData DVD+DL (2.4X) using my NEC 3520A. This is in my MSI mini computer (2.8GHz) running XP Pro. It seemed to copy OK but it wouldn't verify and CD Check reported it couldn't read anything right. If you then use Explorer to try to read the disc it reports that you have a blank disc in the drive. But amazingly, it will play the disc using Cyberlink Power DVD 6 or Nero 7. It is slow to start playing and it doesn't exit very well using either of these programs, but it does play OK right to the end. I changed my Firmware five times (latest is Liggy & Dee NEC ND-3520A 3.06 firmware) in the NEC drive, and the results were the same every time. DVD Disk Info shows it should read every DVD type except DVD-RAM but it doesn't mention DVD+DL discs. It does play original DVD 9 (which are dual layer) movies and Explorer reads the files OK. I have another Computer (1.8 GHz, XP Home) with a PIONEER DVD-ROM DVD-304 SCSI, a SONY DVD RW DRU-510A and a SONY DVD RW DW-D18A. All of these drives read in Explorer OK and play the disc OK using Cyberlink and Nero 7. I ran CD check in the Pioneer DVD-304 and it reported that the disc is perfect. I guess the question is, is my NEC drive defective or is this how a NEC 3520A drive works? Any suggestions are welcome. Thanks, Dave

[Jeremiah58]

The same thing happens occasionally with my NEC 2500.
The drive is certainly not defective, since the disc plays in other ROMs and players fine.