Is this with version 0.7.4 of MLT? Can you try with 0.7.6, available when you add this PPA:
sudo add-apt-repository ppa:sunab/kdenlive-release
Is this with version 0.7.4 of MLT? Can you try with 0.7.6, available when you add this PPA:
sudo add-apt-repository ppa:sunab/ kdenlive- release