My Iphone sounds muffled whenever I usethe microphone. For example, when I play a game, when my mic is turned off it sounds natural, but, when I turn the microphone on, the sounds sound muffled or just gone.

iPhones have two sets of microphones, on the short sides at each end of the phone. Normally you hold the phone so one is directed at you and the other away from you to pick up ambient (background) noise to be filtered from your voice-plus-ambient received by the first microphone. If you hold your phone, or place it in a location, or use a cover with a flap that causes your voice to be detected by the ambient noise microphone, your voice may be included in the filtering and sound faint.

If the microphones on your iPhone, iPad, and iPod touch aren't working - Apple Support - https://support.apple.com/HT203792

- Clear the microphones

- If people can't hear you on phone or FaceTime calls

- If people can't hear you when you're using speakerphone

- If the microphone doesn't work in a specific app: Settings > Privacy > Microphone.