It's very unlikely Speech Dispatcher creates the sound itself. There should be a process that sends texts to Speech Dispatcher to synthesize. Since you don't hear synthesized text, there is something wrong with your audio system, synthesizer, configuration or maybe even Speech Dispatcher.
Which synthesizer do you use with Speech Dispatcher? Do you use ALSA for Speech Dispatcher audio output? Does the synthesizer work when used standalone? Is there anything suspicious in your Speech Dispatcher logs (see /var/log/speech-dispatcher/)? -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org