Lubuntu volume keys (not working)

To get them work edit the /home/$USER/.config/openbox/lubuntu-rc.xml. Replace the commands within the <command> statements to:

<!-- Keybinding for Volume management -->
 <keybind key="XF86AudioRaiseVolume">
 <action name="Execute">
 <command>amixer -D pulse sset Master 5%+</command>
 </action>
 </keybind>
 <keybind key="XF86AudioLowerVolume">
 <action name="Execute">
 <command>amixer -D pulse sset Master 5%-</command>
 </action>
 </keybind>