Hi,

I have this problem, when I play back a clip in kdenlive it is almost ok only very slight crackle in the audio but when I scan through the clip it takes a wile to catch up.  If I add an effect then the hole thing gets very jittery and very hard to use.  It would apeare to be ok once renderd but thats not very helpfull when trying to put to gether a larg clip as I have to render it to see what it looks like. 

I'm running:

Hard ware:

Dell XPS M1530

4GB RAM

2.10GHz intel core 2 Duo T8100

nVidia GeForce 8600M GT

Software:

Ubuntu 8.10

Kdenlive 0.7.2.1 (Installed using synaptic package manager)

I have used the repostorys here 'deb http://ppa.launchpad.net/baudm/ubuntu intrepid main'

I have also tried purging Kdenlive and lib files using this:

1. apt-get remove --purge kdenlive libmlt* inigo swh-plugins frei0r


2. apt-get update


3. apt-get install kdenlive dvgrab swh-plugins frei0r

from the forum.  I have also tried changing the video and sound drivers in settings>>configure kdenlive>>play back

but this had no effect.

Most likely, the combination of project setting,  source video file format, and effects does not allow for realtime playback. You could render a specific section of the timeline and choose the option to play it as soon as it is done.