The topic of syncing video and audio is usually just associated with timecode jamming for audio and video. Many starting out or even intermediate sound mixers aren't aware of the advantages of using Genlock and Timecode together.
Let's quickly sum up both and not get bogged down in too much jargon and scientific background for now, I'll save that for another post.
This counts the number of frames per second and is usually a super accurate clock that includes the frame data.
This syncs the internal camera crystal that pulses to generate the actual frames. If these are even a few fractions of fractions of frames off from each other it can cause problems later down the lines, especially for Live broadcast.
Sync both for best results
If you are controlling the sync of the frames firing and the counting of how many frames you will be rock solid on syncing not only audio to video but camera A to camera B.
as always you can let me know your experiences down below.