How to reproduce: 

1. Wear any helmet that is enchanted with Respiration 3.
2. Put yourself underwater and look at the animation of the bubbles slowly popping. Do not enter swimming mode or move around, otherwise you have to exit and re-enter.
3. Notice that the pop animation is very jittery, goes back and forth, and sometimes plays multiple times for one bubble (you might have to wait a 2-3 bubbles for it to happen).