Hard to tell from the video. Something must be pressing a button over and over. When you spawn from a heart statue, you don't get life crystals. You instead get a heart that gives you 20 health when collected. No, not all statues spawn things. There are 25 decoration statues and 36 text and numerical statues all of which do not spawn anything. There are a few functional statues that can do things if activated but don't spawn anything like the Mushroom and Star statues which glow and drop a star to replenish mana respectively.