Things to check:
- Does talking motion have any X movement value?
- If you click the animation settings for the idle & talk sprites (the small film clip icon), do they both have a the same frame size, and a number of frames that make sense?
- Is this a new layer that you've created since the last update, or is it carried over from an older setup?
If you like, you can send me your layer set.xml file on discord (@rahisaurus) and I'll take a look.