Solving Audio and Video Sync Issues

Another issue that FCP users sometimes encounter is audio and video going out of sync during playback. There are several different causes, from mistakes in your settings to the very nature of DV and QuickTime. Determining whether the problem you encounter is progressively or consistently out-of-sync will give you your main clues as to why this is occurring and what you can do to address it. First let's look at what progressive and consistent mean in terms of audio and video sync.

Out-of-Sync Audio and Video Problems at a Glance
Type of Problem	Symptom	Possible Cause	Solution
Audio and video progressively out of sync	#1: Clips go rapidly out of sync and exhibit audio artifacts	Incorrect capture or sequence settings	Correct your capture or sequence settings; page 746
	#2: Correct capture settings, but clips go slightly out of sync after several minutes, and a red or green line appears in the Timeline above the clip	Nonstandard sample rate in recording device	Convert your audio sample rate; page 746
Audio and video consistently out of sync	#1: Monitor playback is consistently out of sync with output device	Bus latency (the pathway to the output device is delaying the signal)	Adjust latency between your monitor and output device; page 748
	#2: Video and audio sent to separate devices are consistently out of sync with each other	Bus latency (the pathway to the output device is delaying the signal)	Adjust latency between your output devices; page 750
	#3: Audio consistently out of sync when using a Panasonic AG-DVX100 camera	Missing DVX-100 Audio Sync tool plug-in	Install the DVX-100 Audio Sync tool in the plug-ins folder; page 751