>>richar+(OP)
Is someone's voice their IP? Is it more-valuable property because they are famous? What type of IP? Trademark? Without their name and image in combination, is a voice/likeness actually defensible?
Training a computer to have any actual-human sounding voice is likely to almost match someone's voice.
I haven't taken an IP class since 2004, but I'm not sure if there's a real case here is there?