I am only guessing it is a sowftware hickup, but I do not know how to go on from now. I have no idea how to solve this, but it is a real problem, since I can't communicate with either of my freinds/family/teammates properly without a working microphone. The Master bar is 'fixed' the minimum, it is grey and I found no way to turn it or move it any way higher. In Audio Midi Setup, I found that both in Input (I suspect it happens only when my headset's mic is not plugged in, but I am not 100% sure about that) When I switch to Input from Output, the bar shows at about 60% 'blue' for a split second, and goes all the way down in an instant. In System Preferences/Sound/Input, the bar behaves like this: (in case the links don't work, I describe with words as well) The funny things I found are look like these: The microphone jack on the mac mini 'looks' clear, no dust, the small steel balls are in the right place, and I mainly plugged in and out my headset into my keyboard, so that couldn't cause the problem either. Tried to install Line In, and uninstalled properly afterwards, tried the toothpick trick no, no, no. I tried the Sound in System Preferences, also the Audio Midi Setup, both failed. plugging headphones in and out (they don’t appear as an option either) rebooting the audio in the Activity. Step 4: Release all keys and allow your Mac. I’ve looked for results and tried: restarting computer. Step 2: Hold down the Cmd + Alt + P + R keys while powering your Mac on again. My sound output works flawlessly, I can listen music, watch video, all the above mentioned ports are working as far as output goes. Hi When I tried to use my laptop this morning, the internal speakers and mic weren’t working and no longer show up on the System Preferences. I have microphone jacks on my keyboard and also on my speaker system, my headset worked in all of them, and out of the blue, it won't. My mac mini (2,5GHz i5, Radeon 6630M) worked without an issue so far, and all of a sudden, it's microphone jack stopped working.

Macbook built in microphone not working