Lip-syncing mouth drawings disappearing, not maintaining proportions when I scale them

Hey everyone, I’m trying to use auto lip-syncing and it seems like all goes well, the sound file comes in perfectly, the mouth types I mapped out switch out at the right frames, but the drawings come in as all different sizes, when I scale them down on each frame and play the sound back, they go right back to their old sizes (either massive or microscopic), and some of them disappear and don’t even show at all; I set a motion keyframe from the beginning to the end, maybe it’s the peg set-up, also the mouth isn’t rigged to the basketball (which I plan on rigging like a head; the character will be a talking basketball), is that what the problem is? I figure it has to be something with the pegs, or the fact that the mouth is a separate layer, or something but this is pretty irritating as you can imagine. Any help would be greatly appreciated!