Am doing a readout of Random generated string for captcha purposes(in ASP.Net C#). I have implemented this using Adrian's solution using System.Speech.SpeechSynthesizer in the following link
How to implement Custom Audio Capcha in ASP.Net
But my client is not happy with the voice as it is clumsy some times. For example J is read out as G.(I have managed to split the string into character array and substitute J with 'jay' which reads it correctly). Since it is a server we are going to put this on, the number of voice that is installed is just one, which is Microsoft sams. So am looking for any other option which will read it out better. I cannot use a third party service or API(like recaptcha) as it is a banking website(you know security reasons)