Just to let you know: for me the issue is resolved. In the dev. console of the launcher I find that download job "Resources" failed to execute for the first time I've played MC after applying the 1.7.2. So I've restarted launcher and waited about 30 seconds to resume the download job "resources" (this can be related to busy servers) but after the job was succesfully completed all the sound works fine.
Just to let you know: for me the issue is resolved. In the dev. console of the launcher I find that download job "Resources" failed to execute for the first time I've played MC after applying the 1.7.2. So I've restarted launcher and waited about 30 seconds to resume the download job "resources" (this can be related to busy servers) but after the job was succesfully completed all the sound works fine.