Low Microphone Volume
Some third-party iPhone cases cover the microphone or the top microphone on the iPhone 4. Remove the case and make some calls to see if the caller can hear you better. Play some music to see if the volume is better.
When you first received your iPhone, a clear protective plastic film covered the display for protection. If you have not removed this film, make sure it is not covering the microphone or speaker. If so, remove it completely.
Sound Muffled When Speaking Into the Mic
Check the volume setting on the iPhone. The volume setting buttons are on the left side of the iPhone. You can adjust the volume by pressing the buttons up or down.
Check that the microphone mesh covers and top microphone holes are not dirty and clogged with debris or lint. If so, use a clean, small, dry soft-bristled brush to clean the holes out.
Very gently brush the microphone mesh with the brush. Make sure you brush away from the 30-pin dock connector so you do not brush any lint into the dock connector.
Clean the Headphone Jack
The Apple iPhone headphones that come as standard are good headphones and get the job done for most. While they will never please audiophiles, for most of us, they work just fine. One of the best features of the Apple iPhone headphones is the mic button that allows you to control music while having conversations.
If the mic stops working on the headphones, and you call Apple support, they will probably send you a new pair. In many cases, however, it’s not the headphones that are causing the problem.
In a lot of cases the headphone jack is dirty. You can take the end of a paperclip and see what you can find in there. It is very easy for lint to get caught up in there, or whatever else is lying around in your pocket. Gently use the paperclip to clean out the hole and try the mic again. Make sure you completely power off your iPhone before you do this. Use a flashlight and shine it down into the hole and see if you can see any lint or anything.
If the iPhone 4 microphone doesn't work it can be caused by application conflicts. Updating the operating system on the iPhone can correct this problem. This update is free through iTunes. If the microphone is still not working after this update, the problem is more than likely hardware and you will need to seek the help of a certified Apple technician. Here are the steps for updating your iPhone software.
- Remove the iPhone from its case, as the case could be blocking the microphone.
- Connect the iPhone to your computer via the USB cable. Plug one end of the cable into your iPhone, and the other end into a free USB port on the front or back of your computer.
- Open iTunes by double-clicking the iTunes icon on your desktop. Alternatively, open iTunes through the Start menu.
- Click the iPhone listed in the sidebar on the left in iTunes, and then click Summary.
- Click Check for Update and then click Download and Install to update your iPhone software.
- When the update is completed, disconnect your iPhone from your computer. Insert the headphone jack into the headphone port on the iPhone.
- Tap Phone from the home screen, tap Contacts and then select a contact to call.
- Adjust the volume level of the microphone by pressing the + button on the left side.
If the microphone on the iPhone is still not working, take your iPhone to a Apple store to be serviced.
If you have a jailbroken iPhone then Apple will not replace it for you. When you jailbreak an iPhone it completely voids the warranty. Here are a couple of extra things to try.
- Check if there is anything plugged into the headset port, such as headsets or headphones, that may be using the speaker.
- Make sure that mute is disabled while you are talking.
- If there is a Bluetooth headset nearby that you are using or it is turned off, tap Settings on your iPhone, tap General and then tap Bluetooth.
- Hold down the Sleep/Wake button until you see slide to power off to restart your iPhone.
If you have tried everything else and the mic is still not working, you can try to restore your device. You may want to call Apple before you go through a complete restore, however, especially if your iPhone is still under warranty and has not been jailbroken. You can take your iPhone to any local Apple retail store no matter where you purchased your iPhone 4.