Sounds like it is an issue of Poser crosstalk. 

When this happens, is V4 the first figure/object in your scene?  Have you tried injecting the character's body INJ first and the head INJ last?

If you right click the pose window, are you running "OpenGL" or "SreeD"?  Try "SreeD" if you in Open GL.

 

"It is good to see ourselves as others see us. Try as we may, we are never
able to know ourselves fully as we are, especially the evil side of us.
This we can do only if we are not angry with our critics but will take in good
heart whatever they might have to say." - Ghandi