What happens is there are some very small (a little bigger than a speck of dirt!) resistors on the RF track that have a tendency to come unsoldered and fall off the board. The only place I know that can or will repair it is PDA Repair World. It is not very expensive to have it done, but you will have to call them because I do not see it offered on their site. I have a friend that had the same problem and they repaired it for him.
The speaker is blown. It is very common on that model. The good news is it is easy to change. It uses the same speaker as a 8700. They are pretty old. If iFixIt does not have it, I know PDA Repair World sells them and even offers a replacement service. Might be something to look into if you want to repair the phone.
Alot of times, the camara actually pops loose out of the socket that is it plugged into. This can happen if the phone is dropped. If you remove the battery door, you can actually put your thumb over the lens of the camera and hold on to the front of the phone and push in on it with moderate force. You can actually feel it click back into place. If that doesn't work, you might need to send it to PDA Repair World or something to have the camera replaced or the board repaired.