For instructions on how to update the firmware, please refer to this article here
The DM Smart DSP software is used with the DM-608 and DM-810 processors and the D-4.800 and D-6.1200 DSP amplifiers.
You must first uninstall the existing software version on your computer before installing the latest version.
Right click on the DM Smart DSP software icon in the Start menu and select “uninstall”
Or, you can go to your control panel, select “Programs”, then “Programs and Features” and select “Uninstall”. From there, you would select “Uninstall”.
After the software has been successfully uninstalled, you will need to download and install the latest software version from the appropriate product page on the AudioControl website for the DM-608/810 or D-4.800/D6.1200.
From here, it’s just like installing the software for the first time.
For instructions on how to install the DM Smart DSP software, please view the article here