Hey notheguyyouthink, those are just "tabbed" buttons to show you the features. Purely aesthetic and just a button for "sign up".
I would second the parent comment though in thinking you might be able to improve the user experience if everything that seems clickable actually is. It might take a little css tweaking only.
Regardless, this seems technically quite impressive.
This would explain why some are clickable and some are not.
Am I misunderstanding you? Seems like a strange aesthetic choice, almost like the real buttons (ie Recording and Forwarding) are hidden next to the fake buttons haha.