Buttons in imported swf, not working fine

hi ! i am facing a problem with buttons.
when i call a swf into a projector, the buttons in the swf don’t work fine. the imported swf is a slide presentation. once the NEXT button is clicked, the mouse needs to be displaced from its current position , otherwise the button does not click again.
if i move the mouse and then come back to the next button. it works fine, but then it has to be done everytime i want to move on to the next screen.
can anyone tell me why does this happen? i have already put _lockroot for the imported swf.