Apple iphone4s microphone malfunction play Music no sound what to do

The specific symptoms are as follows:

1. Phone calls have sound, voice calls, open loudspeakers also have sound.

2. Listen to music silently, see movie silent. (All audio and video playback are silent)

3. The volume key can only be conditional on the volume of the bell, but not the music volume.

4. There is no problem with the iphone headset.

The study of the above symptoms may have been caused by system file evaluation errors.

Then use the 91 Assistant iOS Pro, enter the file management directory/system/library/privateframeworks/iap.framework/support/, delete the file iapd, and then enter the directory/system/ library/launchdaemons/, delete the file com.apple.iapd.plist, and then restart the machine.

Note: Please make a backup before deleting the file to avoid any problems that can be restored in time.

In addition, if the above method has not been resolved, you can try to delete the iapd,iap2d,com.apple.iapd.plist three files at the same time, and then restart the machine.