Anyone know why blocking the Macbook Air's internal microphone hole (using a tape or finger) seems to almost completely disable recording? Surely, sound should penetrate through the metal case. Could it be that when the hole is taped, OSX thinks all sounds are ambient noises?

EDIT: Covering the microphone hole on my LG G3 phone hardly does anything though.

  • Just a thought...Have you never put your hand over the mouthpiece of a phone? when you block off the microphone, how is sound supposed to be registered?
    – Allan
    Feb 18, 2017 at 17:06
  • @Allan Covering the microphone hole on my LG G3 phone hardly does anything though.
    – John M.
    Feb 18, 2017 at 17:13

2 Answers 2


So the answer to this question involves 8th grade science. So brace yourself. The answer has to do with the change of medium for the sound waves to travel through. Solids can conduct sound much better than air in truth but the transition between the two states of matter requires a decent amount of energy to switch so by covering it you are trying to make it change not once but twice as it hits the outside and changes to move through the solid then hits the air and thus you expend much of the energy. This reduces the volume and can even negate it all together. (Ever heard of sound proofing? This is the concept of it they just find a substance that absorbs the energy rather than allowing it to pass) So now knowing this you may just want to remove the case or get an external mic. like the rest of us. Sorry for the lengthy answer.


Covering the microphone will indeed reduce your ability to make a recording (check in System Preferences -> Sound -> Input; there is an option for using the "internal microphone" as an input, but none for "metal case").

Might I suggest simply uncovering it for the purposes of making your recording and then covering it back up afterwards?

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .