WPF

<Grid>
        <Expander Name="expander1" Margin="10" IsExpanded="True" Background="Silver" 
                  Collapsed="expander1_Collapsed" Expanded="expander1_Expanded">
            <Expander.Header>
                <Image Source="E:\Tutorial\FullComponent\Ajax Loader\ajax-loader2.gif"></Image>
            </Expander.Header>
            <Expander.Content>
                <Button Margin="20" Height="30" Name="button1" Click="button1_Click">Click Me</Button>
            </Expander.Content>
        </Expander>
    </Grid>

private void playAudio()
{
objAudioConferencingPlayer.StartAudioPlayer(IncommingAudioStream);
}

public void StartAudioPlayer(byte[] AudioStream)
{
	if (!IsPlayerRunning)
            {
                StopPlaying();
                m_Player = new WaveOutPlayer(-1, fmt, 16384, 3, new 
   BufferFillEventHandler(Filler));
                IsPlayerRunning = true;
            }
            m_Fifo.Write(AudioStream, 0, AudioStream.Length);
}

private void Filler(IntPtr data, int size)
{
 if (m_PlayBuffer == null || m_PlayBuffer.Length < size)
     m_PlayBuffer = new byte[size];
            if (m_Fifo.Length >= size)
                m_Fifo.Read(m_PlayBuffer, 0, size);
            else
                for (int i = 0; i < m_PlayBuffer.Length; i++)
                    m_PlayBuffer[i] = 0;

            System.Runtime.InteropServices.Marshal.Copy(m_PlayBuffer, 0, data, size);
            // m_Fifo ==> m_PlayBuffer==> data ==> Speakers
}