I had a similar problem after replacing my battery. After I put the phone back together, my bottom speaker was not working. I went ahead and ordered a speaker to replace the one that was not working, and it still didn't work. Knowing that my top speaker was working okay, I replaced the top speaker to see if the new one I received was working, and it didn't work on top either. As a matter of fact, I put back the original top speaker that was working okay, and now it doesn't work. So now neither one of them are working. I have to use earphones to hear my phone. I don't know what happened. The instructions to replace the speakers are not that difficult.
Does anyone have any suggestions on what I should do? I'm not ready to give up my phone just yet.