Hello,
I wrote my DVDs with Firmwares 0037-0039 and tried to play them on my Yamakawa 715. (with Matsushita drive - they used diffent drives for this player)
The source were some Buffy-DVDs (Season 6, but I don’t think that matters at all)
The first disc was a Platinum DVD-R, which played back without problems.
I had a few optodisck001 DVD-R, I could partly play back. But for these discs, my Toshiba 1612 DVD-ROM with Nero CD-/DVD-Speed showed errors on the discs. Same result with my Tayio Yuden from Fuji and my MCC from Verbatim.
A few DVD+R discs (Speer Data, don’t remember the MID-codes) were readable with my Toshiba 1612, but not with my Yamakawa. The same goes for DVD+RW with the RiDATA disc that was supplied with this drive.
Unfortunately I was not able to test DVD-RW because 2 out of 2 burns were unsuccessful and the discs could not be used afterwards. (Princo and PrimeOn - the only discs I could get at all)
I used several Programs to write the DVDs like DVD Decrypter, Nero or Pinnacle Instant Copy, but that made no difference. Maybe my player accepts DVD+R(W) with booktype set to DVD-ROM, but lacking firmware support for that, I was not able to test. 