Hey,
You are right.
We can get back the sound of iPhone simulator, by do some setting in Audio MIDI Setup app.
The only thing you are wrong is we do not need to reboot the Mac.
The correct procedure to get back the sound of iPhone simulator is as the following:
Step 1:
Go into the 'Utilities' folder and run the app named 'Audio MIDI Setup'
Step 2:
Choose the left Audio Device tab at the top.
Step 3:
Press the rightmost button 'config device' (my mac os is Chinese version, I translate the word to English) at the middle.
Step 4:
Un-tick all device in the second column of table, so that no audio device to be used at this moment.
Step 5:
Only tick the build-in microphone to use for audio device. Press Done button.
The iPhoneSimulatorAudioDevice will suddenly come out now if it was disappeared before.
Step 6:
Choose iPhoneSimulatorAudioDevice as default input audio device.
Press the close button. Then, you simply get back the sound of iPhone simulator. The sound effect for OpenAL should work fine now.