`latest.log` from 1.11.2 starting up with OpenAL error and no sound.
I can confirm that this problem still exists in 1.11.2. In particular, the "Unable to initialize OpenAL. Probable cause: OpenAL not supported" error is present. I can provide the logfile, but it's essentially identical to the one above, down to the line numbers in the stack trace.
Note that reinstalling minecraft and reinstalling mac OS (10.12.2 "Sierra") did not fix the problem, which is consistent with it being an incompatibility with the version of OpenAL in Sierra.