Before Salsa actually dances, a short tune named Dance! plays. This is basically the background beat for Laugh! Be Happy!.
If the player presses the wrong button, Salsa will start dancing, but not correctly. This will result in the door staying shut, and a severe electrocution from Fassad. When that happens, What Happened?! will play. It's just Laugh! Be Happy! gradually slowing down and fading out.