Absolutely no sound playing, even if volume is maximized

After downloading and installing a fresh version of Minecraft 1.4.5 or 1.4.6, no sound happens whatsoever. Pressing F3 + S does not fix the issue.

My sound sliders are all the way up and I am using the default LWJGL and LWJGL Mac native files.

To recreate:

1. Back up minecraft folder
2. Delete minecraft folder
3. Force update to grab all of the latest files
4. Create a new world (Game mode and world type don't matter)
5. Walk around, try to play music discs, light TNT, or do anything else that is known to cause a sound event.
6. Notice that no sound happens.