On my 3rd generation iPad running 6.1.3 I can hear sound when I change the ringtone option in Settings > Sounds. I can't hear sounds when I listen to music, Youtube or videos online while in Safari. I can't change the level of sound using the volume control on the right-hand side. After restoring the iPad I am still in the same situation. Any suggestions on how I can back my sound listening to music, etc are appreciated.