No sound in menu/game
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All sound should be downloaded before the game starts using the new launcher. You could try deleting the following folder:
~/Library/Application\ Support/minecraft/assets
That will make it download the sounds again.

I have been having the same problem...Lost all my sounds in Minecraft and in Feed the beast. they use separate launchers and different instances as well do they share the LWJ thing for sound? I am running Umbuntu not sure what the problem is but would sure like some help.

Is this still a concern in the current launcher version?

Assuming no longer a concern.

Yes it is still a issue.
On Mon, May 6, 2013 at 9:08 AM, [Mod] Tails (JIRA) <
Hmm... I'd say duplicate of MC-11030, but Jeb's comment there is interesting:
Given that this is happening with the new launcher, it may be something they intend to revisit.