Ok, got it. this is what is happening
Your calculation on rollout is creating a problem
function betterOut(evt:MouseEvent):void{
**better_mc.gotoAndPlay(27- (better_mc.currentFrame-10));**
}
This expression sometimes returns frame number 28 which is ahead of your 'stop()' which is at frame 27 and so it goes on playing the whole click animation.
27- (better_mc.currentFrame-10)
Try the simple solution of adding 'stop()' before your click animation starts i.e. frame 31 in this case.
See if this sorts your issue.