Buttons that grow in size on rollOver

hi,

i have a series of buttons next to each other on 1 line.

On rollOver each button grow a bit in size, on Rollout they shrink again to their original size.

Now this all works fine, as long as i exit my buttons towards the top or the bottom. When i leave my button to the left or right, i move over another button. That second button now also grows, and this somehow prevents the button i just exited to shrink. I think it is because the second button is “arranged more to the front”. Can this be? Any ideas how to fix this?

thanks!