How can I capture audio in Blazor Server?

My app: https://vcat.azurewebsites.net/voice

uses azure voice to text service on a blazor server side. It works fine locally, but when published at azure it does not work.

What is wrong?

As I have understood it is not only me who has this problem. This is another one: CognitiveServices.Speech Blazor Server not working when Published to Azure

here is the code:

private async Task record()
    {
        try
        {
            _isRecording = true;

            _question = string.Empty;
            _answer = string.Empty;

            using var audioConfig = AudioConfig.FromDefaultMicrophoneInput();
            using var speechRecognizer = new SpeechRecognizer(_speechConfig, audioConfig);

            var speechRecognitionResult = await speechRecognizer.RecognizeOnceAsync();
            _question = speechRecognitionResult.Text;

            _isRecording = false;

            if (string.IsNullOrEmpty(_question))
            {
                _question = "Please try again!";
            }
            else
            {
                //_isThinking = true;
                await answer();
                //_isThinking = false;

                await speak();
            }
        }
        catch (Exception ex)
        {
            Error?.ProcessError(ex);
        }

    }