This covers an audio sync issue you may unknowingly experience in blender at some point if you render using audio+video settings.
Specifically this is an issue experienced after successfully lining-up and playing everything properly on vse playback. It occurs because the sync during the actual render follows different rules than vse playback. It's important to note this if you render out longer videos, such as those over 10 minutes in length. Based on stack exchange threads, your individual system settings might affect how noticeable the sync issues may be. I can only speak from my system's experience and the online readings of others. So run your own tests if this is of concern. In 2.79b I've been able to replicate it back to back over 2 different projects. I honestly don't recall it always happening, but currently I'm able to replicate it so it 'always happens'...so just be cautious of it occurring sometime if it isn't already.
More specifics about other possible solutions, etc, over on youtube. Thanks.