In case Emacs gets completely crazy and refuses to run commands including C-x C-c because of a bug in speechd-el or in an alternative output related custom definition, you can try to invoke the following command as the last resort:
Try to disable all modes, hooks and wrappers installed by
speechd-speak
(speechd-unspeak
).
The following commands are rarely used, mostly for diagnosing purposes:
Repeat the last output text
(speechd-repeat
).
Prompt for a text and read it.