public void Synthesize(string content, VoiceConfig voiceConfig, bool ssml = false, double pitch = 1.0, double speakingRate = 1.0, double sampleRateHertz = Constants.DEFAULT_SAMPLE_RATE)
        {
            SynthesisInput synthesisInput = null;

            if (ssml)
            {
                synthesisInput = new SynthesisInputSSML()
                {
                    ssml = content
                }
            }
            ;
            else
            {
                synthesisInput = new SynthesisInputText()
                {
                    text = content
                }
            };

            _textToSpeechManager.Synthesize(new PostSynthesizeRequest()
            {
                audioConfig = new AudioConfig()
                {
                    audioEncoding   = Constants.DEFAULT_AUDIO_ENCODING,
                    pitch           = pitch,
                    sampleRateHertz = sampleRateHertz,
                    speakingRate    = speakingRate,
                    volumeGainDb    = Constants.DEFAULT_VOLUME_GAIN_DB
                },
                input = synthesisInput,
                voice = new VoiceSelectionParams()
                {
                    languageCode = voiceConfig.languageCode,
                    name         = voiceConfig.name,
                    ssmlGender   = voiceConfig.gender
                }
            });
        }