iPhone 4 internal mic active during phone call with headphones

How do you know if internal mic is on or not? What is the indicator?

I've noticed that too, and it happens whether I use the supplied headphones or the headphones which came with my iPhone 3G. The internal microphone was not active when I used headphones on my iPhone 3G.

Followup: I called Apple about it. It happens intermittently for me, including when I was on the phone with Apple support. After a few tests, I'm restoring the software onto the phone to see if it's a software thing, and if it still happens, I'm going to do an exchange.

Sounds like a software bug. Did you restore as new phone or from backup? Try restore as new phone (I know, it's a pain).

This also happens to me. It makes the phone call very noisy with a loud echo. It happens with apple headphones and sennheiser-strangely I didn't notice it on the first couple of phone calls made with the headphones but now it's every call. I'm reluctant to do a full restore as new phone unless I have some evidence that it will work!

You're not plugging in the headphones the right way

I really really really don't want to restore as a new phone. It's not so much anything saved within the apps but its my collected SMS messages which I don't want to lose. (There's some good stuff in there I don't want to lose.) Is there any way to archive the SMS messages on my computer, because if so, I might give that a call just to try.

What is the 'right way'? Surely the headphones are plugged in or they aren't? Can you explain?

Has anyone tried restoring as new yet and seeing if this fixes it?

I have not. However, I found that rotating the plug in the microphone jack will start/stop the internal mic, so I think it's some hardware thing where whatever triggers the internal mic to shut off isn't being triggered appropriately.

I've noticed it too, using a set of Shure earphones with no mic.

It's most noticeable when you're in an area with very loud ambient noise, such as walking down the street.

I've noticed it only when on a call while driving. Problem occurs with supplied earbuds -- and my favorite V-moda Vibe Duo which worked fine with 3G. If car is not moving, all is well. Once I'm moving, get repetitive static that maps to sound of tires going round & round. AARGH! I use my phone a LOT when driving, so this is a big deal. (Sorry, Oprah...)

At least I have a better understanding now. Any sense of whether this culd be addressed with software?

Message was edited by: derryhumma

I have this problem too and it's really annoying. I have Shure earphones which isolate out outside noise, and connect them through a third party cord with a microphone and clicker on it to the iphone. I have tested this with multiple of these cords, including a monster one I got today at the apple store. In all these cases, the inline microphone's input gets sent through my headphones, and depending on the level of noise it can make it almost impossible to hear the other person in the conversation. THis must be a software/iphone hardware thing because the only way I would be able to hear it is if the iphone's amplifier was taking in the microphone's sound and then adding it into the headphone audio feed. I would like to see a fix for this in their next update . . .

Following up on my issue, I went to the Apple Store and they swapped out my iPhone 4 for a new one. The new one doesn't have the headphone jack issue and works fine. It seems to work fine in all other ways. So, folks having problems like this might want to look into a trip to the Genius Bar.