Pioneer DVR-111 Dual Layer Problem - HELP!

Can anyone help. I have just purchased a Pioneer DVR-111 Burner and I have just attemped my first burn with a Verbatim Dual Layer DVD-R 8.5GB disc using DVD Next Copy, but with no success. I have updated the firmware to the latest version of 1.19. I can burn to DVD-R 4.7GB disc with no problem. Could it be I’ve got a faulty drive, or is it a media issue and I just need to wait for a new firmware release from pioneer? The drive is set master on IDE port 2. If anyone can help or have any suggestions it will be much appreciated.