This video shows the method to sync sound using Sony Vegas. This is important in case of double system sound when audio is recorded separate from the picture. The first step involves opening up the poorer source of audio like the audio from the built in microphone in the laptop. Now open the good quality audio like the one from a camcorder just below the first one. Align the two audio using a reference mark. In the given video, it is the clapping of hands recorded on both audio. So, the spike in the audio is used to align the two videos. This can now be superimposed on the bad audio to play with the video. This finishes the task.