Starting this morning out of the blue my husband's s4 has no sound when calling in or out. He has made sure the speaker works (pandora) and it does. He has called my phone and you can hear my phone ring but listening thru his phone you can't hear the ring, when I pick up and say hello he hears nothing and I can't hear him talking. He can text and do everything else. He's tried calling voicemail and no sound either. Any ideas before we call VZW?