The speaker phone on my iphone 3g no longer produces audio. The speaker itself works for playing music and listening to voicemails, but the in-call speaker phone function does not work. When you touch the speaker phone when I'm on a call the audio completely cuts out. The speaker phone has worked previously on my iphone. I also have never dropped the phone, so I don't think that the issue. I have tried a restore and no luck. What are your thoughts? Thanks.