Color bumps on command keys

Hi,

I have a problem every time i try to create a white flash command key on hog 4 (a roadhog). I create it and it al goes well until i try to use it. 1 or 2 times goes wel, but after a couple times it will stay white instead of the color i wanted it to be. How can i make shure the button keeps flashing instead of the entire fixture going to white?