After plugging in my headphone into my iphone 4s no sound comes through. I can hear the music from the phone itself. Do I need to change the settings?
Maybe you are not pushing it in all the way. I thought mine were defective until I pushed harder than I thought I should.
If you have any kind of phone protector make sure the jack hole opening is not not obstructed by the cover! You might have to stretch the cover hole a little to push headphone jack all the way in! That was my problem it works fine when in all the way.