Sorry but I can't tell anything from your video. I have to see the project. The most likely culprit is that you have some weird things going on with your cache. Whenever you have a preview or a render that doesn't come out right purge everything and try again.
If that doesn't fix it then please describe your workflow in detail. There's not much tweaking in your keyframes. IOW, several frames of one position and then several frames of another. When you time remap video like that you can end up with some very odd frame interpretation because there's not much information to go on. If I only had two keyframes for hand position then I would put them one frame apart and then pre-compose and time remap. You would now be able to get any speed of movement you want. If there are no keyframes for movement of the arms or the body but these are just two still images then you can't expect time remapping to solve problems.
So here's what you do. Try purging memory and cache. If that doesn't work show us the timeline with the properties of the time remapped layer, the pre-composed animation, revealed by pressing the U key twice and describe exactly how you are animating the layers that are giving you problems. I suspect that it's just an incorrect workflow that is causing your problems.
Thanks for your help.
I cleared the cache and that didn't work. Also some very similar issues seem to pop up at different places when I open the file, so I think you're right, it seems to be something with my workflow.
Here's the tutorial I followed to do this.
Every frame you see is a Photoshop file made to be one frame in length, spaced out, and then using a keyframe hold and time remapping in a nested composition, just like the "lip-syncing" in the tutorial above. For each character there's two compositions, body and head, and each of those have the "frame" composition where the time-remapping is from. Thank you for your patience, I'm a student and fairly new to this.
We'll use "Mike" (person on the left), who has similar issues on certain frames:
Composition holding the head and body comps. His head moves in certain place to match when the body changes. There's a few different positions his body moves, like he will lean to the side so his head moves with it:
The Head comp. Each Hold Keyframe you see is changing the frame to match the mouth movement of the lyrics:
That Head comp's original composition with 1 image for each frame, this is where I'm time-remapping from:
I agree with what's been said above - move your reference frames apart so they aren't back to back. AE might be trying to tween your time remaps using the previous or following frames which could result in some strange looking results. It looks like you might benefit from one of the lip-syncing friendly scripts that give you expression controls for frame referencing. See if you can find something at aescripts.com that would simplify your animations.
Redoing everything would be quite the headache. This whole video is finished, I just have these minor render issues.
Out of desperation I tried a few different things: Spacing out the frames from the "Phonetics" and "Body Frames" compositions so that there was a space between each frame, tried changing the FPS of certain compositions (they were originally all 25fps), and I've tried toggling all the hold frames on then off again. This fixed some of the render errors and created new ones.
Again, the actual hold frames are working just fine, even when I render them. It's when I nest those compositions into other compositions that I get these render issues. The compositions are all the same frame rate. Is there something else I'm missing?