This works in Manjaro Xfce 64bit
- Enable event sounds and input feedback sounds in Settings > Appearance > Settings tab
- Go back to All Settings and scroll down to select Settings Editor
- Click on xsettings in the left column, and change the SoundThemeName value (by double clicking it) to the sound theme folder name in /usr/share/sounds/.. e.g. freedesktop
- Make sure your System Sounds volume is high enough
- You can add more sound themes from http://xfce-look.org/index.php?xsortmode=alpha&page=0&xcontentmode=25
- To get the startup and shutdown sounds to work -> http://pclosmag.com/html/Issues/201305/page09.html