This posting is older than 6 months and can contain outdated information.
Thanks for asking.
Remote Buddy can't detect when XBMC's internal volume changes or when
a button press triggers a volume change in XBMC. If that's what you'd
like to do, please turn to the XBMC team. I'm sure they're open to
your suggestion.
If, however, you have a dedicated button to change XBMC's volume on
your remote, you can simply change the action associated to it at
Prefs > Mapping > XBMC to "Audio & CD/DVD > Increase System Volume"
and "Audio & CD/DVD > Decrease System Volume".
For more information on changing the mapping and how mapping buttons
work, please see the Help that comes with Remote Buddy.
Best regards,
Felix Schwarz