I just got my iMac back from Apple—they had to replace the video card for me—and the internal mic is not working. In System Preferences -> Sound, I can select "Internal Microphone" or "Line In" and I get nothing on the volume bar for either when I speak. I moved the input volume slider all the way to right and I still get nothing, but oddly enough as I move the slider I register sound. Only while the slider is moving though.
I went to Utilities -> Audio MIDI Setup and made sure that the inputs were not muted. I also tried a few combinations of the "Format" options (44100.0 Hz and 96000.0 Hz each with 2ch-24bit, 2ch-20bit, and 2ch-16bit) but still no dice.
I went in to Garage Band -> Preferences -> Audio/MIDI and made sure that "Built-in Microphone" was selected under "Audio Input". Still no dice.
I tried restarting and pressing [command] + [option] + p + r until the third startup noise. I am not sure what this is supposed to do, but I found the suggestion on a forum somewhere. No dice.
Does anybody have any suggestions for what else I might try to get this working, or how I might find out for certain if the mic is broken? If my mic is broken, does anybody know of a good video or article detailing how to replace it on your own?
I would not be terribly surprised if Apple broke my mic during the repair since they made several other errors and I had to bring the computer back to them twice before the original problem was fixed.
EDIT: I plugged in an external mic that I own and the computer seems to be receiving sound through that. Any suggestions as to how I can go about fixing the internal mic?
Best Answer
My guess is that they accidentally disconnected the mic or failed to reconnect the mic when they operated on it.
MacFixIt has a guide if you want to try to take it on yourself. They rate is as "Moderate" difficulty.
Be sure to double check that I got the right model for your iMac.
Otherwise it's back to Apple it goes...