SimpleTextToSpeech

using var api = GetAuthenticatedClient();

using var memoryStream = new MemoryStream();
await foreach (var streamEvent in api.Audio.CreateSpeechAsStreamAsync(
    model: CreateSpeechRequestModel.Tts1,
    input: "Overwatering is a common issue for those taking care of houseplants. To prevent it, it is"
           + " crucial to allow the soil to dry out between waterings. Instead of watering on a fixed schedule,"
           + " consider using a moisture meter to accurately gauge the soil's wetness. Should the soil retain"
           + " moisture, it is wise to postpone watering for a couple more days. When in doubt, it is often safer"
           + " to water sparingly and maintain a less-is-more approach.",
    voice: (VoiceIdsShared)VoiceIdsSharedEnum.Alloy))
{
    if (streamEvent.SpeechAudioDelta is { } delta)
    {
        byte[] chunk = Convert.FromBase64String(delta.Audio);
        memoryStream.Write(chunk, 0, chunk.Length);
    }
}

byte[] bytes = memoryStream.ToArray();

FileInfo fileInfo = new($"{Guid.NewGuid()}.mp3");

await File.WriteAllBytesAsync(fileInfo.FullName, bytes);

Console.WriteLine($"Audio available at:\n{new Uri(fileInfo.FullName).AbsoluteUri}");