Sound will stop working out of no where?

So my phone will be fine all day, and then all of a sudden the sound will stop working? i cant hear the little clicking when i type, text tones wont come in, the lock button doesnt make that shutting noise. Sometimes it happens after i plug it into my computer. I have tried blowing into the headphone jack, but that didnt work? I updated it, i restared it... i dont get it?? please help me!!!