By default, Huddle Hub connects to the update server when switched-on or rebooted. You can also check for an update by entering the Web Console, and selecting Huddle Hub -> Check for Updates.
The firmare can also be updated manually. Please go the the Downloads page, download the latest version and un-zip it on your computer. From the Web Console, navigate to Huddle Hub -> Load Update and select the <HHO_x.x.x.x.dat> file you just uncompressed. The new firmware will be installed and the unit rebooted.