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If you have distorted Sound issue on your iPhone --> If you hear no sound or distorted sound from your iPhone, iPad

If you are not able to hear the other person, click this...>If you can't hear a person on a call or voicemail or if the sound isn't ...

If you only hear through speaker phone mode --> If your iPhone is stuck in headphone mode - Apple Support

If the other person is not able to listen to you then please click this--> If the microphones on your iPhone, iPad, and iPod touch aren't ...

If the above options do not mitigate the issues then Contact your carrier and then Contact Apple Support

Apple Support Community Forum

This is Apple Support Community forum, for user to user interaction for information & idea sharing between users, if need be, extend support on technical knowhow in handling Apple products from more experienced fellow user, This is not the right forum to discuss with Apple Inc.