public function sendXMLRPCMethodCall($methodName, $parameters = [])
    {
        if (!array_key_exists('Content-Type', $this->headers)) {
            $this->headers['Content-Type'] = 'text/xml';
        }

        foreach ($this->headers as $header => $val) {
            $this->client->setServerParameter("HTTP_$header", $val);
        }

        $url = $this->config['url'];

        if (is_array($parameters)) {
            $parameters = $this->scalarizeArray($parameters);
        }

        $requestBody = xmlrpc_encode_request($methodName, array_values($parameters));

        $this->debugSection('Request', $url . PHP_EOL . $requestBody);
        $this->client->request('POST', $url, [], [], [], $requestBody);

        $this->response = $this->client->getInternalResponse()->getContent();
        $this->debugSection('Response', $this->response);
    }