I just rang the Apple support line as all the same problems happened to me - No texting sound no incoming text alert no music unless I had my head phones in but the phone did ring with my personalized music ring tones and no swishing when I unlocked the phone.
I was told to got to settings - then sounds - then at the top this page is Silent and I had that on - he told me to turn it off and everything came back - very ODD as it was alway had that button on before, so not sure why, but hey it works again - now I just have to see if its the same issue on my husbands phone as the same thing has happened to him. If in future I want the phone on silent I just use the physical button on the side.
Good luck hopefully a fix for you all!