Was just googling around and found that the Samsung support website links to N-D. Check out the bottom of this page:
Pretty funny that the would link to my page, which was an archive of their page in the first place.DVD-N501 (NUON)
DVD-N501 (NUON) upgrade is for Audio / Video sync issues. This firmware can be downloaded from the NUON-DOME website.
Before downloading and installing the firmware for your player, you should first determine your current version.
1. Turn your player on WITHOUT any software in the disc tray.
2. You will see "loading" appear in the upper right corner followed by "no disc".
3. Press the and buttons on the front panel at the same time.
If your players version is 50 or less, it needs to be upgraded. Please thoroughly read the instructions provided on the NUON-DOME website prior to downloading and installing the firmware upgrade.