Audio on MacBook Air not working, despite audio output being set on "Internal Speakers" in settings.

I have no audio output on any channels: No soundflower output, no output to headphones, and no output to internal speakers. I have made sure that in settings, audio output is set on "Internal Speakers", and not set to anything else. The internal microphone works fine and the microphone on my headphones also works fine when I plug them in.