ZSH: The first letter of a command gets repeated

[Hermann]

Hi,
from the beginning of my use of Speakup on GRML, I observe a strange
thing:
When I type any command at the prompt, the first letter is spoken twice,
so taht, if you have a two-letter-command, you hear three letters - the
first one twice.
It only happens when using ZSH and in no other app. When I call bash
Speakup speaks correctly.
Can someone confirm this? Are there any work arounds?
Hermann

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