Variable Text shifts when changing states

We have dynamic buttons that have changing text when clicked.We would like to use variables for the clicked state, but when you click the button to the new state, the text shifts down and to the right.

So:

Normal - text is $$option_a$$

rollOver - text is $$option_a$$

Down - text is $$option_a$$

Clicked - text is $$option_a_updated$$

It seems to be influenced by the mouse--the text doesn't move until the mouse is moved.

The problem doesn't happen with the state change if text is hard coded, only when variable.

I tried moving disable the button to the top of the code, but this didn't make any difference