Email Notifications on Thunderbird were not working.
I checked the preferences, selected a sound and tried to play it to no avail. It seems that some sound libraries necessary to get sound notifications to work with Thunderbird were not installed. You would think it would feature prominently in Thunderbird's documentation unless it is there and I couldn't find it.
I delved deeply into the KDE desktop's settings fixed some defaults for the default sound device all to know avail. What was weird is that any time I attempted to test the notification sound, the system switched to the default sound device which is not working on my system.
It seems that the sound libraries used by Thunderbird for notifications are not part of the default installations on some distributions. My problem was solved by installing libcanberra-gstreamer, discussed here - http://askubuntu.com/questions/141765/no-sound-with-thunderbird-12-0-1
In fixing it I wound up learning more about the notification process then I expected to and discovered this links which I am placing here for future reference.
Notification related links
Notifu - command line notification for Windows programs
forum thread with example of using XAuthority as alternative to libnotify
Desktop Notifications Specification
Growl (original, Mac version) - http://growl.info/
Growl for Windows - http://www.growlforwindows.com/gfw/default.aspx
Growl for Linux - http://mattn.github.io/growl-for-linux/
Snarl (for Windows, same function as Growl) http://snarl.fullphat.net/
Audio playing related links, command line in particular
sox - to use play command for
ffmpeg - also contains ffplay
mplayer - graphics
In-depth coverage of 3 Popular Command Line Music Players for Linux
Covers music players Cmus, Mp3Blaser and Music On Console
Title should properly be console graphics / ncurses graphics players
curses based music players