Chosen Solution
As happened to Brooke a few years ago, and a number of other people on the web, I can no longer adjust volume on my Macbook. Boo. :( One day while leaving the office, I unplugged my headphones, unplugged my Thunderbolt display, and put my computer to sleep - not necessarily in that order. When I got back to my house, I was prevented by the OS from adjusting my volume:
There are two devices available to me when I have the display plugged in:
It does not matter which I choose. When the display isn’t plugged in, the display audio device is not an option. I could still adjust the volume level through the Sound preferences pane, just not the volume keys. Suggestions on the previously-linked answer and elsewhere on the web have included poking the headphone jack repeatedly with a toothpick. Unfortunately, after I tried this, I now have no sound at all, except, strangely enough, the volume-changing “plick” when I move the slider in the preferences pane. I have to say I’m at a bit of a loss. Suggestions?
I would first boot the computer from an external source like your installation disk or an external drive and check if the sound works on the external OS. If the issue is a hardware issue it could also be caused by a faulty keyboard since there’s a sound control generated by the keyboard. To test this you have to remove the bottom panel, disconnect the battery then the keyboard from the logic board, connect the AC adapter and start up the machine via the two power pads. If you have sound then the keyboard is bad.
Try putting a pair of headphones in, then removing them. It may help. Otherwise, reinstall OSX.
Have you tried resetting your NVRAM settings. Review this Apple TN
If you have setup an external speaker program, like SoundFlower, then that might be the problem. To fix this, go to System Preferences > Sound> and then select Internal Speaker.
If you have a Macbook Pro turn your computer off then locate your Control, Option and Shift keys then turn your computer off then hold all three keys then hold down the power button and keep all four button depress for 20 sec after 20sec then turn your computer on normal and that should fix the problem. it worked for me i have a 13" Macbook pro.
