Cepstral Community

After downloading and installing the Allison-8kHz Telephony voice for use with Asterisk 1.4 and Festival, I created a test extension for TTS such that it answers the call, reads a line of text, and hangs up. The Allison-8kHz voice, however, is severly distorted. Here is a link to a wav sample:

http://www.dssit.com/allison/Allison_distorted.wav


Any help would be appreciated.

Thanks,
Ben