Thanks Arthur & Tom from KDENLive on this easy fix

From: http://www.kdenlive.org/forum/audio-issues-076-ubuntu-910

Kdenlive sound passes through SDL.

If you are using PulseAudio, you need to install the SDL PulseAudio package for it to work, the package is called libsdl1.2debian-pulseaudio

1) open terminal
2) type in "sudo apt-get install libsdl1.2debian-pulseaudio"

Should work fine now.

http://www.ubunite.com (less info)