Q:

windows RT / Universal app, Text to speech "Save as Mp3"

I'm trying to make a speech to text universal app but got stuck on one thing.  I looked all over the internet and could not find a proper solution which works.. So I came here.. Basically I want the app to save what ever is in the text box as mp3.  Here is my code so far:
 private void Speak_Click(object sender, RoutedEventArgs e)
    {
        SpeakText(Text. Text);
    }
    public async void SpeakText(string TTS)
            {
                SpeechSynthesizer ttssynthesizer = new SpeechSynthesizer();

                //Set the Voice/Speaker
                using (var Speaker = new SpeechSynthesizer())
                {
                    Speaker. Voice = (SpeechSynthesizer. AllVoices. First(x => x.Gender == VoiceGender. Female));

                    ttssynthesizer. Voice = Speaker. Voice;
                }

                SpeechSynthesisStream ttsStream = await ttssynthesizer. SynthesizeTextToStreamAsync(TTS);

                //play the speech
                MediaElement media = new MediaElement();
                media. SetSource(ttsStream, " ");
            }

A:

I think you can save SpeechSynthesisStream as just a .wav file.   Then you can re-encode it to anything you like using a MediaTranscoder class. 
MSDN: Media Transcoder
Sample Project using Media Transcoder -- use it as a refeence

Some extra help saving the stream to a wav file : SpeakText.xaml.cpp

