I was able to setup Sipdroid with Google Voice for incoming and outgoing calls on my Samsung Galaxy Player 5.0. I'm able to have a conversation if I have the player up to my ear. The only issue I'm having is when I'm on a call and try to turn the speaker on, I can hear the person I'm talking to, but they can't hear me. I noticed when not on the speaker it uses in-call volume if I try to adjust the volume, but when I turn the speaker on it uses the media player (which may be what is causing the problem). Does anyone know a solution for this?