If this doesn't work try re-creating a new world and disabling sounds. From what I hear their is a bug with the sound files not working correctly on all systems. The game runs fine, other than small freezes that happen every seconds and they freeze the game for seconds and then returns I have Windows 7 Professional bit and I have downloaded 64bit Java, but no help, I tried setting Javaw.
But then Minecraft, The lowest requiring game, lags. Remember Me? Need an account? Register Now.
