For buttons not identified, such as multimedia and others on your PC, to try as follows steps.
Install xorg-xev xorg-xmodmap, open a terminal and type
xev | egrep -o "keycode.*\)"
press interested and note the corresponding code that appears in the terminal eg
keycode 176 (keysym 0x0, NoSymbol) create a text file as association table to each keycode code F between F13> F29
one my example
keycode 176 = F26
keycode 174 = F24
keycode 160 = F25
keycode 222 = F29
keycode 178 = F28
keycode 236 = F27
saved as..xmodmap in your home eg. / Home / tux / .xmodmap
care to remember after the corresponding key on the PC which you assigned F value
edit the file with leafpad / home / tux / .config / openbox / rc.xml
using as a prefix for keys Fxx
my example file
cut.....
</keybind>
<keybind key="F8">
<action name="Execute">
<command>mtpaint -s</command>
</action>
</keybind>
<keybind key="F25">
<action name="Execute">
<command>amixer set Master toggle</command>
</action>
</keybind>
<keybind key="F26">
<action name="Execute">
<command>amixer -c 0 set Master 5+ unmute</command>
</action>
</keybind>
<keybind key="F24">
<action name="Execute">
<command>amixer -c 0 set Master 5- unmute</command>
</action>
</keybind>
<keybind key="F29">
<action name="Execute">
<command>poweroff</command>
</action>
</keybind>
<keybind key="F28">
<action name="Execute">
<command>firefox</command>
</action>
</keybind>
<keybind key="F27">
<action name="Execute">
<command>thunderbird</command>
</action>
</keybind>
</keyboard>
…..cut
were added to hot-key
grab-screenshot F8
mute F25
vol-up F26
vol-down F24
poweroff F29
firefox F29
thunderbird F27
important to create new application startup / home / tux / .config / openbox / autostart.sh
add this line
# Xmodmap
xmodmap / home / tux / .xmodmap &
xsession logout and login to apply
end of modding bye.
