NEC 2510a dvd burner not working after maddog flrmware flash

Help! Think ive destroyed my drive. It no longer burns dvds correctly. I used a firmware flash to try to get it to use maxell dvd- discs, (some - discs it would write to and other makes it wouldnt but it is a dual format drive). Someone told me to update firmware but now when burning it burns the movie files, or a backup dvd, but when played on a standalone dvd player the sound is ‘underwater’ sounding. It will play fine thro the pc but not a standalone. I ran nero toolkit and it now says the drive will not accept dvd+ disc as before…can I ‘reset’ the drive to its original state??

Go here and flash either the 205C or 2A5C firmware.
http://liggydee.cdfreaks.com/page/2500/