Why does my iPhone 4 keep going to mute?

[iMore Question]

I need help!, My iphone 4 keeps going mute

whenever i plug in the charger for my iphone4 it goes mute, even when the usb side is not connected into anything it still goes mute, and when i'm in videos it goes as if it's plugged into a stereo or an external source, but when I tried connecting it to my friends car to listen to it there it just said error 4.

 

[lackster2]

Re: I need help!, My iphone 4 keeps going mute

This might narrow it down...

https://support.apple.com/en-us/HT204770