Hello, over the years of using Kdenlive, I encounter this same recurrent issue. It's never gone for good and can always be counted upon to return, someday. If I take a video and use a separate sound recorder, I need to syncronize those on the time line. Easy enough. But, what happens is that the sound and video gradually lose Sync. and an ever increasing pace. The longer the video the more out of Sync. the video and audio will become even though they are perfectly in Sync. a the beginning of the video. I do realize thta Kdenlive is actually a family set of software (e.g. MLT) that must work together. I'm using Precise 12.04. and Kdenlive 0.9.8. By now, there must be some consensous of what generally causes this problem as it has been around for so long. I need to fix it so that I can complete my stuff, of course, but I'm interested in gaining a deeper understanding of what is this vexing issue. Thanks.

Hmm...Is the sampling rate of the audio not a multiple of 48 (48kHz, 96kHz, 192kHz)? Pretty sure that's more standard for video than 44.1kHz, and that's probably what Kdenlive expects. More on that: http://www.larryjordan.biz/solving-prob ... ont-match/

Maybe there's a setting to shift that?

Kdenlive doesn't have a specific fix for the 44.1khz / 48kHz problem, but you can change the sample rate and adjust the length of the clip in audacity.

Some audio recorders, such as the (older model) Zoom H4, also have problems with gradually falling out of sync - what equipment are you using to record?
For any audio that is to be synchronised, always set your audio recorder to 48kHz, with a lossless codec like WAV, FLAC, or AIFF. Your camera should record 48kHz by default.