Error setting up platform cast

Hi all.
Im new to HA, and cant quite work this out. Unfortunately im not a python guy.

Its installed on a pi running alpine linux.

Any ideas here?

Traceback (most recent call last):
  File "/usr/lib/python3.6/site-packages/homeassistant/helpers/entity_platform.py", line 82, in async_setup
    SLOW_SETUP_MAX_WAIT, loop=hass.loop)
  File "/usr/lib/python3.6/asyncio/tasks.py", line 358, in wait_for
    return fut.result()
  File "/usr/lib/python3.6/site-packages/homeassistant/components/media_player/cast.py", line 190, in async_setup_platform
    import pychromecast
  File "/root/.homeassistant/deps/lib/python3.6/site-packages/pychromecast/__init__.py", line 11, in <module>
    from . import socket_client
  File "/root/.homeassistant/deps/lib/python3.6/site-packages/pychromecast/socket_client.py", line 23, in <module>
    from . import cast_channel_pb2
  File "<frozen importlib._bootstrap>", line 971, in _find_and_load
  File "<frozen importlib._bootstrap>", line 955, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 665, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 674, in exec_module
  File "<frozen importlib._bootstrap_external>", line 779, in get_code
  File "<frozen importlib._bootstrap_external>", line 487, in _compile_bytecode
EOFError: marshal data too short```

Thanks!

Just to add - pychromecast works when i run it from CLI

Python 3.6.4 (default, Mar 2 2018, 16:15:08)
[GCC 6.4.0] on linux
Type “help”, “copyright”, “credits” or “license” for more information.

import pychromecast
chromecasts = pychromecast.get_chromecasts()
print (chromecasts)
[Chromecast(‘192.168.1.40’, port=8009, device=DeviceStatus(friendly_name=‘’, model_name=‘Chromecast Ultra’, manufacturer=‘Google Inc.’, uuid=UUID(‘’), cast_type=‘cast’)), Chromecast(‘192.168.1.21’, port=8009, device=DeviceStatus(friendly_name=‘’, model_name=‘Google Home’, manufacturer=‘Google Inc.’, uuid=UUID(‘’), cast_type=‘audio’)), Chromecast(‘192.168.1.8’, port=8009, device=DeviceStatus(friendly_name=‘’, model_name=‘Chromecast’, manufacturer=‘Google Inc.’, uuid=UUID(‘’), cast_type=‘cast’)), Chromecast(‘192.168.1.22’, port=8009, device=DeviceStatus(friendly_name=‘’, model_name=‘Chromecast’, manufacturer=‘Google Inc.’, uuid=UUID(‘’), cast_type=‘cast’))]

(i removed the names and UUIDs just because.)