I have no external speakers and no volume controls

My external speaker doesn't work for notifications or ipod audio. It only vibrates no matter what type of notification sound is selected. Incoming calls come through the speaker ok. I cannot control the volume with the side volume buttons unless I am in the Settings>Sounds screen and if I move the volume on the touch screen first. Of course the mute button on the side upper left above the voume controls is not on. Also, the setting under Settings>Sounds>"Change with Buttons" is "ON". I have reset the iPhone and the nothing has changed. I know the volume buttons work because when I plug the earphones in, it will control the volume up or down. I feel it is a software issue or setting. Any ideas? I have not found a fix in any forum yet, but I am still looking. I am familiar with the iPhone as I have had a few different models. I have another iPhone 4 that works fine. Please help.