iPhone 4s, sound works on calls and texts but not in music or apps?

[iMore Question]

I updated to iso 9.3.4
I checked all the settings
volume buttons don't seem to function when making a call or in an app, but they work in settings

 

[pkcable]

The volume button works while in settings, OR the slider works? Because it COULD be your button has broken, I had that happen to me on an iPad once. What I started doing was using the accessibility controls from the control panel. That is, go to Settings, General, then Accessibility, then AssistiveTouch, and turn it on. This will give you on screen controls.