Audio problem: The ghost of Christmas past says "these are but shadows... they are what they are - do not blame me." Her mouth keeps moving after she stops speaking.
Suggested correction: No, it doesn't. When she finishes this speech at 45:16, there is an immediate cut to Scrooge. We can only see the back of the ghost. Her mouth is not visible.
Suggested correction: A mouth can move without speaking, not an audio problem but a puppeteering problem that is not a mistake.
A puppeteer problem would still be a mistake.
Maybe for the puppeteer, but in the movie it is no problem because a mouth can move without sound coming out. So what exactly went wrong?
But practically speaking people (or puppets) don't just flap their mouth open and closed with no reason. The overwhelming probability is simply that there was a dubbing error or a line was cut and the dialogue didn't fit with the mouth movement.
The mouth opens 1 extra time. That's all.
But it's glaring enough to be noticeable. Regardless of how or why it happened, it's a mistake.
In the version on Disney+, there is an immediate cut to Scrooge as the spirit finishes her speech. We only see the back of the spirit's head. Are you seeing something different on other versions?
https://www.youtube.com/watch?v=hBDqCFyugW0. I got the scene right here, it's at 1:50. Judge for yourself. I can repeat that part over and over again, but to be honest, sometimes it looks like there is an extra movement. Sometimes I can't see it. Even if it was, muppets move their mouths without speaking all the time.