My IPhone 4s ringer, text, and some apps won't sound
Here's the details.
I have an IPhone 4s, and I use Pinger EX, a VoIP app. My ringer, my text sound, Facebook notification sound, and some but not all app notification sounds are silent. I don't recall making any setting changes before this happened. I have tried restarting my phone, resetting the settings, uninstalling and reinstalling the Pinger app. No, my toggle switch isn't on mute. The "Do Not Disturb" option is off. I have gone through every setting I can find and can't for the life of me find the problem. I have it set to vibrate on ring so that it at least will vibrate to notify me. Again, it's not on silent. I can go into settings and test, and hear, the ringtone. For the text tone and others, I can only get it to vibrate.
Is this some strange and secret sticky key that I'm unaware of?
iPhone 4S, iOS 6.0.1