Voice chat won't work

Hi all, I’m trying to make a voice chat, but up to now I have failed in all my attempts. I have correctly set up an online session between two players (in localhost using onlinesubsystemNULL). The voice capturing is working since recalling IOnlineVoice::IsRemotePlayerTalking() returns true when the second player joins the game. Furthermore reading this topic I have understood that the method that should play the remote voice is IVoiceEngine::ProcessRemoteVoicePackets(), so I have put a breakpoint on it, and indeed it is correctly executed, but still no sound has been played in my game. So I tried to understand what is the audio device the latter method is using, but as far as I have understood it is created the first time this method is called and attached to the main Audio Device, am I right? Can someone help me?
I’m also wondering if there is a way to redirect this remote audio packages to another audio device or to extract the uncompressed audio data before IVoiceEngine::ProcessRemoteVoicePackets() resets the buffer.

I’m looking to use voice chat and failing like a php programmer, don’t buy that market place item…