Program: 46146
Project: 46146
Buggy source:
public void processMessage(final Message message){
  logger.finest("String_Node_Str" + message);
  if (message instanceof OrbEndCallMessage) {
    if (orbDialog != null) {
      orbDialog.setVisible(false);
    }
    done();
    return;
  }
  if (message instanceof OrbSpeakingMessage) {
    OrbSpeakingMessage msg=(OrbSpeakingMessage)message;
    logger.fine("String_Node_Str" + msg.isSpeaking() + "String_Node_Str"+ msg.getCellID()+ "String_Node_Str"+ presenceInfo);
    pm.setSpeaking(presenceInfo,msg.isSpeaking());
    if (msg.isSpeaking()) {
      nameTag.setNameTag(EventType.STARTED_SPEAKING,presenceInfo.userID.getUsername(),presenceInfo.usernameAlias);
    }
 else {
      nameTag.setNameTag(EventType.STOPPED_SPEAKING,presenceInfo.userID.getUsername(),presenceInfo.usernameAlias);
    }
    return;
  }
  if (message instanceof OrbMuteCallMessage) {
    OrbMuteCallMessage msg=(OrbMuteCallMessage)message;
    pm.setMute(presenceInfo,msg.isMuted());
    if (msg.isMuted()) {
      nameTag.setNameTag(EventType.MUTE,presenceInfo.userID.getUsername(),presenceInfo.usernameAlias);
    }
 else {
      nameTag.setNameTag(EventType.UNMUTE,presenceInfo.userID.getUsername(),presenceInfo.usernameAlias);
    }
    return;
  }
  if (message instanceof OrbSetBystanderCountMessage) {
    OrbSetBystanderCountMessage msg=(OrbSetBystanderCountMessage)message;
    nameTag.setNameTag(EventType.CHANGE_NAME,presenceInfo.userID.getUsername(),presenceInfo.usernameAlias + "String_Node_Str" + msg.getBystanderCount()+ "String_Node_Str");
    return;
  }
  if (message instanceof OrbChangeNameMessage) {
    OrbChangeNameMessage msg=(OrbChangeNameMessage)message;
    username=msg.getName();
    pm.changeUsername(presenceInfo,username);
    nameTag.setNameTag(EventType.CHANGE_NAME,presenceInfo.userID.getUsername(),presenceInfo.usernameAlias);
    return;
  }
  if (message instanceof OrbAttachMessage) {
    OrbAttachMessage msg=(OrbAttachMessage)message;
    attachOrb(msg.getHostCellID(),msg.isAttached());
    return;
  }
  if (message instanceof OrbAttachVirtualPlayerMessage) {
    OrbAttachVirtualPlayerMessage msg=(OrbAttachVirtualPlayerMessage)message;
    PresenceInfo info=pm.getPresenceInfo(msg.getHostCallID());
    if (info == null) {
      logger.warning("String_Node_Str" + msg.getHostCallID());
      return;
    }
    attachOrb(info.cellID,true);
    return;
  }
}

Fixed version (ground truth):
public void processMessage(final Message message){
  logger.finest("String_Node_Str" + message);
  if (message instanceof OrbEndCallMessage) {
    if (orbDialog != null) {
      orbDialog.setVisible(false);
    }
    done();
    return;
  }
  if (message instanceof OrbSpeakingMessage) {
    OrbSpeakingMessage msg=(OrbSpeakingMessage)message;
    logger.fine("String_Node_Str" + msg.isSpeaking() + "String_Node_Str"+ msg.getCellID()+ "String_Node_Str"+ presenceInfo);
    if (presenceInfoAdded) {
      pm.setSpeaking(presenceInfo,msg.isSpeaking());
    }
    if (msg.isSpeaking()) {
      nameTag.setNameTag(EventType.STARTED_SPEAKING,username,usernameAlias);
    }
 else {
      nameTag.setNameTag(EventType.STOPPED_SPEAKING,username,usernameAlias);
    }
    return;
  }
  if (message instanceof OrbMuteCallMessage) {
    OrbMuteCallMessage msg=(OrbMuteCallMessage)message;
    if (presenceInfoAdded) {
      pm.setMute(presenceInfo,msg.isMuted());
    }
    if (msg.isMuted()) {
      nameTag.setNameTag(EventType.MUTE,username,usernameAlias);
    }
 else {
      nameTag.setNameTag(EventType.UNMUTE,username,usernameAlias);
    }
    return;
  }
  if (message instanceof OrbSetBystanderCountMessage) {
    OrbSetBystanderCountMessage msg=(OrbSetBystanderCountMessage)message;
    nameTag.setNameTag(EventType.CHANGE_NAME,username,usernameAlias + "String_Node_Str" + msg.getBystanderCount()+ "String_Node_Str");
    return;
  }
  if (message instanceof OrbChangeNameMessage) {
    OrbChangeNameMessage msg=(OrbChangeNameMessage)message;
    usernameAlias=msg.getName();
    if (presenceInfoAdded) {
      pm.changeUsername(presenceInfo,usernameAlias);
    }
    nameTag.setNameTag(EventType.CHANGE_NAME,username,usernameAlias);
    return;
  }
  if (message instanceof OrbAttachMessage) {
    OrbAttachMessage msg=(OrbAttachMessage)message;
    attachOrb(msg.getHostCellID(),msg.isAttached());
    return;
  }
  if (message instanceof OrbAttachVirtualPlayerMessage) {
    OrbAttachVirtualPlayerMessage msg=(OrbAttachVirtualPlayerMessage)message;
    PresenceInfo info=pm.getPresenceInfo(msg.getHostCallID());
    if (info == null) {
      logger.warning("String_Node_Str" + msg.getHostCallID());
      return;
    }
    attachOrb(info.cellID,true);
    return;
  }
}