Multicam clips drift out of sync

I searched for an answer to this one but found nothing.

Like many others, I often use multicam to sync audio to video. Most of the time FCPX does a good job syncing but there are times that I have to go in and manually sync the angles. No biggie. But I've been experincing problems where I get a multicam all synced up, close out the multicam, the library, the software and ultimately my computer. When I come back and open up everything, sometimes my multicams are out of sync. The clips have drifted.

Its not everytime but it has happened on several occasions.

Is anyone else experiencing this or am I doing something to throw my multicams out of sync?

Also, is there any way to lock a multicam so it can't be inadvertently adjusted out of sync?

Thanks
Chris

Well that is a bummer.

I've never experienced this and do quite a bit of multicam work.

What version of FCPX are you on? What type of camera media? How many angles?

It is a bummer, more of an inconvenience than anything.

I'm using 10.1.2

Footage is from Canon 5D and 7D

Typically 3 angles. 2 video and 1 audio. This last round had 5 angles, 2 video and 3 audio.

I fully admit that user error is probably the culprit but I honestly can't see where I am moving stuff out of place. This is where a lock feature would be nice. When cutting, ketframming and adjusting clips, its easy to nudge something a bit and not realize it until down the line.

What are you using for audio capture? Is it at the same sample rate as the video angles?

What happens if you set a monitoring angle and then synchronized the offending angle to the monitoring angle. Does it work?

Yes, the sample rate is the same. Once i get this project out the door, I'll try to test a multicam to see if I can get it to shift out of sync. Of course, everything I do to recreate the problem won't shift the tracks but as soon as I'm on my next deadline, everything will find a way to move around. :S

Thanks for helping out and I'll see if I can get you some test results.

I had a similar issue recently. A two camera shoot with 5Ds and separate audio record. Just near the end it drifted out of sync. But for the life of me I couldn't get it in sync with one of the cameras. Then I noticed that this camera was dropping frames. I could tell because of some traffic in the background made it obvious. (Cars skipping forward by a frame every so often)

It was a hot day that day and the 2 Cam IV went for a while. One camera obviously was suffering. I guess this is an issue with using DSLRs.

May not be your issue but thought I'd mention it just in case.