Hi! The game has music, at least in more than 6 pcs we've tried physically it has and we used different browsers. Never happened a bug like that so i can tell that must be a problem in your end. You should check and maybe give the game another try ^^"
About the head crack, that mechanic exists so you have to think better on where you launch your head. You'll only receive damage if you fall fast from a high place. Exists to accomplishing the limitation. About the leaderboard... That's a great idea! We hadn't had time to implement that, three days is literally nothing, but of course is a nice idea! ^^
We really appreciate your feedback! You're invited to give the game another try, check your sound and take care of stanley <3