SlackBuildsOrg/audio/pulseaudio-ctl

pulseaudio-ctl (pulseaudio volume control).

Control pulseaudio volume from the shell or mapped to keyboard 
shortcuts.

Is a simple bash script to allow for control of pulseaudio 
without alsautils. Simply map the following to keyboard 
shortcuts in your DE or WM. Xfce4 allows for this under 
Settings > Keyboard > Application Shortcuts.

A config file resides in ~/.config/pulseaudio-ctl/config.

* if you use OpenBox you can control sound multimedia keys 
simply editing ~/.config/openbox/rc.xml