Why won't the sound on my iphone work without earphones?

I have an iphone 4s which is fully up to date, all of my sound is fine when my earphones are plugged in however when i have no earphones in i can't play music or hear any sound when on apps and games etc, but my sound works for facetime and when i'm on the phone to someone even on loudspeaker, it sometimes goes quiet though, i have tried everything i can think of to fix it and nothing will work, please help

That happened to me when I got the speakers on the bottom of the phone wet. I got a new one.

  • Why won't the sound on my iPhone 4S work? I have had my iPhone for 3 months and it has been working fine. I used to share an iTunes account with my sister, and the sound would work on anything on my phone. Now, I made my own iTunes account and the sound for YouTube and iTunes will not work. The volume switch on the side is not set to orange. Any answers would be appreciated!
  • Why won't the sound on my iphone 4 work? When i manually use the buttons to turn it up is says ringer like always but the sound part doesn't show up? And on my ipod the place to turn it up is just black.why? And how do i fix it?
  • Why won't my music play in my earphones on the iphone 6s plus? Really really really irritated. The music just plays through the speakers and not the ear phones. Someone told me before what to do to correct it and it worked, so i know it's not an actual jack issue. Ps worst iphone ever made. I should be able to LISTEN TO MY MUSIC when i want to and not have to call apple every time i need to do a basic function.
  • Why don't earphones work on my iPhone? I have an iPhone 6s Plus, but EVERY time I've tried using earbuds or headphones, no sound comes out. Nothings stuck in the headphone jack, but sound comes out normally whenever I don't have anything plugged in. Even if I put earphones in the adapter, it still doesn't work. Any advice on what I should do?