The voice prompts for some words just aren't 'right' ... like "Jazz" anyway to get it to talk slower or enunciate properly?
You can control the speed of the voice using the hardware options in the Phatnoise software.
If you want more control over how the voices pronounce words, try Phatvoice. Check the Phatvoice section of this forum: http://forum.phathack.com/cgi-bin/yabb2/YaBB.pl?board=PhatVocie
You can also try different voices. Some voices seem to do better than others when pronouncing words.