On my iPhone 4s that is running iOS 7.1.2, I am running into a super-problematic issue: the system sounds (ringtones, text tones, lock/keyboard, etc.) aren't working. Even with the ringer at 100%, and not on silent, none of these sounds are working. This is an extremely big issue for me. Strangely, the vibrations still work, and alarms go off without a hitch. EDIT: When headphones are plugged in, the sounds will go through the headphones with no problems whatsoever. Can anyone help me with this serious issue?