a file when selecting file input as your audio source.');
                return;
            }
        }

        function getAudioConfig() {
            // If an audio file was specified, use it. Otherwise, use the microphone.
            // Depending on browser security settings, the user may be prompted to allow microphone use. Using
            // continuous recognition allows multiple phrases to be recognized from a single use authorization.
            if (audioFile) {
                return SpeechSD