My iPhone 4 sound isn't working. Only the headphones work. What's wrong?

My iPhone 4 sound isn't working. Only the headphones work. What's wrong?

You might have accidentally got it wet, try putting it in a bag if rice for a while. This happens often to iPhones.

This happens when the mic port gets really wet and the phone thinks that you have the headphones plugged in. This is due to residual water in the port. Leaving it to dry under the fan can take care of this!

Okay NEVER GOT THE MICROPHONE PORT THE SOUND DOESN't WORK!