Can't get Larynx working - Thorsten voice not available

hello experts
Have installed rhasspy from a pre-compiled armel .deb file on a pi zero with a seeed 2mic respeaker.
I chose Larynx as tts and rhasspy loaded 3 additional files and installed them. So far so good. When i now refresh the available voices nothing happens until a timeout occurs.
What i see is the message ‘ModuleNotFoundError: No module named ‘gruut’’ whenever ‘pip list | grep gruut’ shows
gruut 2.3.4
gruut-ipa 0.13.0
gruut-lang-en 2.0.0
So I’m currently clueless and hope someone here has an idea what i can do.
The rhasspy log shows

[ERROR:2024-06-07 21:39:41,901] rhasspyserver_hermes: 
Traceback (most recent call last):
  File "/usr/lib/rhasspy/usr/local/lib/python3.7/site-packages/quart/app.py", line 1821, in full_dispatch_request
    result = await self.dispatch_request(request_context)
  File "/usr/lib/rhasspy/usr/local/lib/python3.7/site-packages/quart/app.py", line 1869, in dispatch_request
    return await handler(**request_.view_args)
  File "/usr/lib/rhasspy/rhasspy-server-hermes/rhasspyserver_hermes/__main__.py", line 1716, in api_tts_voices
    voices = await core.get_voices()
  File "/usr/lib/rhasspy/rhasspy-server-hermes/rhasspyserver_hermes/__init__.py", line 940, in get_voices
    handle_finished(), messages, message_types
  File "/usr/lib/rhasspy/rhasspy-server-hermes/rhasspyserver_hermes/__init__.py", line 995, in publish_wait
    result_awaitable, timeout=timeout_seconds
  File "/usr/lib/rhasspy/usr/local/lib/python3.7/asyncio/tasks.py", line 449, in wait_for
    raise futures.TimeoutError()
concurrent.futures._base.TimeoutError
[DEBUG:2024-06-07 21:39:11,860] rhasspyserver_hermes: Publishing 67 bytes(s) to rhasspy/tts/getVoices
[DEBUG:2024-06-07 21:39:11,853] rhasspyserver_hermes: -> GetVoices(id='94c92212-adcd-4cd3-b34c-eb7130d547cd', site_id='default')

any help is appreciated.
Thanks, Jo