So I was listening to music in the shower on my 4s, something I always do, and when I was done I got a drop of water on the screen nothing new it happened a few times. Anyway after I wiped it clean the volume you turned off on my phone and comes back every now and then. Ringtones work and so do text tones, I can also play music when my phone is charging. Everything else is working fine, so I'm thinking maybe the dock connector shorted. I see a dock connector on ebay for $5 so it might be a cheap fix, although Ifixit has it for $35.