Under most played in the smart playlist listed under collection, there are numerous songs listed there that I no longer have in my library and I haven't figured out a way to delete them so that the smart playlists only contain songs that are currently in my library. 

Amarok Version 1.4.3
Ubuntu 6.10
xine Engine
FLACs

Upgrading to 1.4.5 is always a good idea. Maybe it fixes the bug, or maybe not, but it will sure fix a huge heap of bugs in general. You can find a package here:

http://kubuntu.org/announcements/amarok-1.4.5.php