Imported video doesn't sync to audio..

[DrFox303]

I film while playing drums in addition to multi-tracking the session in Pro Tools. However, when I import the video to Pro Tools, after lining them up, they fall out of sync within a few minutes - the video ends up not being the same length/timing as the audio. Anybody know whats happening, or how to fix this?

Thanks!

[simonchase]

Unless two devices are "sync locked" they will drift

There are various ways to do this. But most devices simply don't have the option. Only professional equipment has it, and even then only really high end stuff.

Sync reference, video reference, black and burst, etc