You're right. Some normal Jen Taylor responses are now in all monotone. It's still Jen Taylor when you ask "Do I need an umbrella today?" But if you ask a Halo question, which should obviously bring out Jen Taylor, ie "Where is Master Chief?" it's monotone. Weird.
I am in India and I have Alpha version. It was going perfect till last few days. Then Jen Taylor's voice is gone, Cortana sounds too robotic now. Its like someone replaced her with a zombie. Issue is not resolving. Any solutions so far?