Os6 undate sound not working

1. Double-click the Home button and swipe the Task Bar (at bottom) to the right. Check volume and mute settings.

2. Try a reset. Hold the Sleep and Home button down for about 10 seconds until you see the Apple Logo

My sound has also stopped working after I upgraded to 6.1.3 update. I can only hear sound with the headphones plugged in. Very frustrating!