How to Disable the Mute Button on an iPhoneby Shawn FarnerUpdated September 28, 2017
The mute button on the iPhone, also called the silent switch, is a switch on the side of the device that allows you to mute all sound when in the "on" position. If you have no sound coming from your device and you think you may have accidentally enabled the silent switch, you can learn how to determine the switch's position and turn the mute function off.
Wake your iPhone from sleep using the sleep button at the top of the device, and then perform the "Slide to Unlock" procedure to display your iPhone's home screen.
Flip the silent switch on the left side of the device near the top. If you flip the switch from the "on" position to the "off" position, a bell graphic will display briefly on your iPhone's screen and then disappear.
Play a music file on your iPhone or open an application that makes some other type of sound to ensure that your sound is now working correctly. You have successfully disabled the mute button on your iPhone.