Very odd SAPI 5.1 Text2Speech problem

Hello,

I have a very weird Problem with the SAPI text to speech interface:

I use the Text2Speech API in a  MDI MFC application. I have a little toolwindow (Dialogbased) that "speaks" out text via the SAPI and visualizes the spoken text. The text is sent by the active MDI Childwindow to the dialog via a Registered Window Message.

Here is the code, the problem is described below:

BOOL CVoiceDlg::InitSAPI()
{

      if(FAILED(CoInitialize(NULL))) {
            
            m_strError=_T("Error intialization COM");
            return FALSE;
      }

    HRESULT hRes;
      
      hRes = IpVoice.CoCreateInstance(CLSID_SpVoice);
      
      if(FAILED(hRes)) {
            m_strError=_T("Error creating voice");
            return FALSE;
      }
      
      hRes = IpVoice->SetInterest(SPFEI(SPEI_VISEME), SPFEI(SPEI_VISEME));      

      if(FAILED(hRes)) {

            m_strError=_T("Error creating interest.");
            return FALSE;
      }
      
      hRes = IpVoice->SetNotifyWindowMessage(m_hWnd, WM_RECOEVENT, 0, 0);
      
      if(FAILED(hRes)) {

            m_strError=_T("Error setting notification window");
            return FALSE;
      }

      return TRUE;
}

// This is a test function
void CVoiceDlg::OnBtnClickedTest()
{

      if(!m_strError.IsEmpty() || !IsWindowVisible()) return;

      SpeakChat("squish.squash.the.debug.rat.494_00000", "This is a test", FALSE);
}

// This handles the Registered Window-Message
LRESULT CVoiceDlg::OnSpeak(WPARAM wParam, LPARAM lParam)
{

      CString strName = ((EXT_MSG_STRUCT*)lParam)->lpszParam;
      CString strText  = ((EXT_MSG_STRUCT*)lParam)->lpszMsg;
      SpeakChat(strName, strText, (BOOL)wParam);
      return 1;
}

void CVoiceDlg::SpeakChat(CString strName, CString strText, BOOL bAction)
{

      if(!m_strError.IsEmpty() || !IsWindowVisible()) return;

      if(bAction){

            strOut = strName + " " + strText;
      }
      else{

            strOut = strName + " says: " + strText;
      }

      TRACE("SpeakChat: %s\n", strOut);

      IpVoice->Speak(strOut.AllocSysString(), SPF_ASYNC, NULL);      
}



Here the problem:

When SpeakChat is called from the OnBtnClickTest() method, it works correctly,
but if it is called from the OnSpeak(...) method, it reads the text out twice:

One time with punctuations in the form strName + " " +  strMsg and one time, without
punctioations with the bAction condition handled correctly. The first time, the visualization of the
speech, does not work, the second time it does.

I have verified, that the Window message is send correctly (only once).