It is advised that users of dbx DriveRack® 4800 and 4820 upgrade to System Architect 1.50.3 or higher since this version addresses an issue with dbx DriveRack 4800 and 4820 when loading JBL VerTec® V4 DSP Preset Data.

Use this link to download -

http://hiqnet.harmanpro.com/sa_download.php 
