I have also gotten audio out of synch with video and I'm not sure how that happened to me. I'm not an expert at fixing it but here is a technique that's helped me:

1. Find in your clip the best distinctive sound you can match to a video action. Think the clapboard you see at the start of a production film. The clapboard snaps closed and you hear a sharp click. If you had something like that, synching would be a cakewalk. I have had some success in my videos selecting a single word or syllable like "I" in "I do", noting that you will normally hear the "I" at the point the mouth reaches it's most open position. The start of "I" and the mouth at the open position becomes my synch point. Easier to do than describe.
2. Then highlight a short segment that surrounds your chosen synch point and enable looping. Now play your loop while nudging the audio left/right until the audio and video are perfectly synched. Finally, lock the synched audio and video events together.

-jerry

Seriously, you should devote some energy to finding out HOW and WHY you got the thing out of sync in the first place.
If you're dual head recording then a clapper board is a must have, slating the heads and tails of your shots makes syncing a piece of cake in Vegas even if the two devices have slightly off clocks. Once you have a shot / tape synced on the T/L render out to a new file and edit that, editing is enough of a chore without having to worry about trvial but frustrating, time wasting, mudane tasks like getting audio back into sync. I've done many hours of dual head recordings with overdubs and puch ins and never had a problem but hey I'm an engineer and I force my talent (under threat of death) to give me the space to stay organised and that means slating everything and keeping notes even if they're just spoken to camera.
If you don't have a clapper board just a clap with the hands in front of the camera will do.
And just for a laugh I've had one video to work on where the 'talent' spoke out of sync and another (opera) where they looked for all the world like they were singing out of sync but after I'd 'fixed' it it really was out of sync cause they sing out of sync!
Bob.

When i capture the video and begin splicing and trimming the fat out of the complete video, the audio also gets trimmed. I had 3 cameras rolling for this wedding so i could get different angles so this does seem to pose a problem when editing.

Very good advice Jerry thank you.

T

Bob to be honest, i don't know how i got the video and audio out of sync. The only thing i can think i did to mess it up was when i was trimming out what i did not use for the final cut. I am going to pay closer attention to my splicing and cutting. It was probably something simple that i just breezed over without noticing. Sometimes you want to see the final product and go to fast. Haste makes Chinese films spoken in english.

What I do is set up all three, untrimmed audio/video tracks on the timeline. Sync them up. When you want to make a split/cut just click somewhere off all the tracks (in the grey area) use the arrow keys to move the cursor more precisely and hit the "s" key. This will split all the tracks at the same place keeping the audio with the video. Once you get done cutting everything out click while holding down shift on each clip that is closest to the left side of the timeline with the exception of the clips that are butted up against that part and right click and select all events to the end and then drag them to touch the clips that are up against the timeline. Do this until you have no space inbetween the clips. Now you can color correct, add fx etc and delete the extra audio tracks or keep them- it is up to you.

There is probably a more efficient way to do it, but that is how I do it.

j razz

If I'm recording a wedding and have 3 camera's running (this has only happened twice....I'm still trying to learn "the trade"), I first make certain that I have a really good audio feed. I do this by recording off the sound board at the host church.

When I get home and have all the video to work with I first work with each one seperate and try to line up the audio from the cameras with the audio from the soundboard recording. In general, this isn't horrible. I have yet to have audio from my camera match up exactly to the audio from the board. This ususally requires me to go in and trim the audio in between natural pauses in speach. Once I have the audio files matched up I delete the audio feed from the camera.

It's a little time consuming but it gives me consistent sound throughout the wedding.

ptimp: It also helps to zoom in on the timeline very far. Like seeing the silence/spaces between the notes.

Very easy with Vegas.

Since you can see that the mouths aren't in sync I suggest you look for syncing on what I'll call "key lip positions". These are when the lips come together in words such as "mother", "battery", "pop". So there is a built in clapper when you need it and you can slide the audio into sync. Playing a section in loop will let you make fine adjustments. I've synced wild recordings using this technique and it works perfectly (at least it does when the audio recorder holds precise speed). These key lip positions most clearly let people know when things are out of sync and you can afford some error in other places because it will be less noticable. Noticeable, but less jarring.

Gee, what ever happened to right click clip then select synchronize by moving?

JJK

In those cases where I sense the sync is not quite right, but can't decide on whether it leads or lags, I just intentionally move the audio 3 frames left, then right. Usually, one will look much worse than the other, and I then know which way to adjust the audio.

It could also be that your multiple cameras are not sync'ed to one another. If you're using one camera's picture with another camera's sound, they can be out of sync quite easily.

I always try to sync my cameras to music. It's easy to see on the timeline, and usually has good, sharp transients.

And keep in mind that a camera that's far away from the action can have its sound lag the picture by a few frames, just because of the speed of sound. If you've got the people mic'ed, then your sound will arrive at the same time as the picture.