I'm having this really devlish problem.
Some matchmoved layers look perfectly aligned to my footage in my comp window. However, when I render to Quicktime, some layers are slipping early or late by one frame. I've manually moved layers forward or back in time a frame so it looks incorrect in the comp window, but it'll render out correctly. It's a repeatable problem for this project. I get the same results with MP turned on and off.
Any ideas about this one? I have this wild idea that it's a rounding error in how 23.976 footage is handled in viewer vs render? (Because RAM Preview looks correct)
I can't post any frames because it's under NDA.
Mac OS X 10.8.3 / AE CS6 22.214.171.124 / 48GB RAM / Radeon HD 5770
This may be unrelated, but you're missing the 11.0.3 bugfix update to CS6 that might help.
Is your workflow 23.976 all the way through? ie., 23.976 source footage, 23.976 comp, 23.976 render.
Or is there a mixture of 23.976 and 24?
When you mix frame rates that do not evenly divide into each other, there is probability that AE will choose a different frame than you're expecting. (The math is correct, even if the result is unexpected.)
However, I would not expect the comp and the render (export) to differ from each other if they are using the exact same frame rate. So unless that's the case, something else is likely to blame. For example, is there any time stretching/time warp involved or do you have any time-dependent effects applied?