Symbol doesn't flow well

Created a symbol which involves some moving buttons. Seems to work well when I’m creating it, but when I view it in the browser it’s jerky in spots.

Can’t see any timeline stuff that would cause the problem.

I’m attaching it here. Would appreciate any (132.1 KB)

It’s difficult to see what your animations are with the exported file. Could you share the Hype document? To me … the buttons are changing z-index which may or may not be part of the animation. This is the only thing I could see when viewing the output.