Lip sync with null's

[VERNON302838217atn]

Trying to Lip sync with a null layer but have no clue how to! every time i do the mouth either dissapears. It works if i move it by a single gone. I need help, please

[ShiveringCactus]

I'm struggling to understand what your comp set up is.  You have a null layer with position keyframes(?) which are set from lip sync, but when you attach a mouth it is disappearing?

I think a screenshot showing your entire set up would be really helpful here.  

It's most likely that the position values are big enough that the mouth is off screen, but without being able to see the problem, I can't say for sure.

[VERNON302838217atn]

"You have a null layer with position keyframes" Yes. i do. The Position key frame at the beginning has it set to 0.00,0.00. If i move it past 0.24 it will blank out but only show 2 of the mouths on the 9 frame mouth composition

[ShiveringCactus]

If I'm right, that is a very unusual set up.  It looks like the position of the null layer is driving the Time Remap values of the mouth precomp.  But there'll only be so many frames in the mouth precomp, so when you move the position layer too far, it is pointing to non existant frames.

I'd suggest taking a look at the expression on the Mouth precomp - My guess is it's a linear expression.  That will show you the minimum and maxium positions you can move the null for.  (post here if you get stuck)

You might be better replacing the null position with a slider or better yet, if you have Character Animator, use that to create time remap lip sync values for After Effects.

[VERNON302838217atn]

Okay thanks. I'm quite new to after affects and there wasn't a tutorial on how to use a null layer as a slider. Thank you