Respectfully, I don't believe it is me. I have read other posts where people are running into the exact same thing. From what I have read, I was able to get the voices to work shortly by loading the Paul voice, then the Kate voice. This works for a little while. It does not explain why the Sam voice, half way into a conversation, would go silent. Especially when I wasn't doing anything else but talking with Hal. Nor should I have to do any of the tricks involving the registry and other risky and complicated things to make a product shown in a huge ad on Hal's product plug in page to work partially. I'm sure many don't have any problems with it as I have heard this before but then I am not running Windows 98 on an out dated computer.
None of this justifies what I paid for the voices, only to work sometimes if I stand on one leg and wish really hard.
As far as solutions. Perhaps the SAPI5 engine. Perhaps conflict with other sound devices. Perhaps it's the V word. Vista. You know, the same Vista that if you listen to other folks, has caused this global warming thing and is the reason why we have disease, war and poverty in the world. That Vista.