Quiet Audio on iPhone 4 Video - Microphone Problem

This is hopefully to help some of you with quiet audio problems. I was afraid that my iPhone 4 was having microphone problems because the videos I was taking had very muffled audio - almost silent. I googled and found many threads with people complaining about problems with mic audio and speaker audio. In almost every single case, everyone told them to take their iPhone back to Apple. I didn't read any success stories.

Now that I noticed that the audio in my videos was so quiet, I realized that I had been having trouble with people hearing my with I used the phone on speaker as well. I was about to give up and take it back to Apple, when I decided to double check. I found that the iPhone 4 has two microphones. There is one at the bottom, and one at the top next to the headphone jack.



This top mic is the sneaky one! This is where the audio is captured for the videos you take, as well as where the audio is captured when you are using speaker phone. Once I knew this, I realized my mistake. I had installed a DecalGirl skin on my phone recently. Upon further inspection, I noticed that the skin completely covered the secondary mic hole! I was about to be upset that they would make such an oversight, and then I noticed the tiniest, almost invisible perforation where they had pre-punched the hole! You would have to have know it was there or you never would have noticed it. I used a thumbtack to poke it out and now my audio is crystal clear.



I realize that not everyone with mic problems has a skin, but I thought this might possibly help someone searching for answers. Check that your case has the appropriate holes and that the holes aren't blocked. Also make sure you aren't covering the secondary mic when recording video (easy to do in landscape mode).

Nice find! I didn't realize that mic was used for anything other than noise cancellation. How did you figure out that it is used exclusively for videos and speaker phone?

From it not working when covered! =P Also the Apple website talks about it.

I dont think so...i just made a test recording while completely covering up the mic hole you speak of, and my audio is still crystal clear. I think its captured by the bottom mic.

Voice recordings use the bottom mic. Did you do a video?

I did. But to be fair, I also did a second test (video also) covering up only the bottom mic, and it's still crystal clear, so now I'm just confused.

Try it. Record a video normally, then record a video with your finger covering the top mic. It will be virtually silent.

Is that the decalgirl all over White? Is it the matte one? If so could you put a few pics up of the phone front and back? Thanks

See This thread.

But how come my audio is crystal clear when i take a video and cover up the top mic, then? Im using an Apple bumper, and i cover the mic tightly, and my audio is fine.

That's why. You're using the bumper, so there is a good amount of space between the hole on the outside of the case and the microphone itself. Take the case off, and cover the hole completely flush against the phone. Then you will see.

Hi !

Thx for this post. I had a similar prob. A was about to reinstall my iPhone & return it eventually.

P.S. I've made account just to say thank you!

Your right I just did a test video it went muffled when I covered.

Great! Glad to hear it was helpful to someone. Thanks for creating an account to say so. Feel free to stick around. This is a great place!

I was worried, coz I suspected my top mic was damaged after an incident which is, one store executive tried to penetrate a pin into the top mic hole thinking that is where its supposed to penetrate to eject sim tray(dumbass). Now your post helped me to check whether my top mic is working or not - amazingly it works. Thanks bro.
Test 1. Took a video without covering either mic. Result : crystal clear sound.
Test 2. Took a video with covering top mic only. Result : very dim sound.
Test 3. Took a video with covering bottom mic only. Result: crystal clear sound.