I have a galaxy 3 (I think it this should work for other android devices too.) Anyways. dropped my phone in a toilet while changing a couple days ago. As soon as it fell in I got it out. And dried off the screen and (this is gonna sound weird.)
the first thing I did was: I started sucking out the water from the headphone jack , volume buttons, power buttons , homescreen button , speaker and lastly micro USB port. The second thing was: I made sure water didn't get on the battery and dried the inside. The third thing was : I made sure the speaker was working. It did. *if the speaker doesn't work make sure you sucked all the water out of it* but my galaxy works the same. Maybe you should try this. Thanks for reading! c: