: Error executing script. Unexpected error for call_service at pos 1: Expecting value: line 1 column 1 (char 0)

i trying to play audio file to volumio but i keep getting an error

the script i have is

alias: "!!play audio to warning volumiio"
sequence:
  - service: media_player.play_media
    data:
      media_content_id: http://pump:8123/local/mixkit-facility-alarm-908.wav
      media_content_type: music
    target:
      entity_id: media_player.warning_volumio
mode: single

the error i get is

!!play audio to warning volumiio: Error executing script. Unexpected error for call_service at pos 1: Expecting value: line 1 column 1 (char 0)
Traceback (most recent call last):
  File "/usr/src/homeassistant/homeassistant/helpers/script.py", line 451, in _async_step
    await getattr(self, handler)()
  File "/usr/src/homeassistant/homeassistant/helpers/script.py", line 684, in _async_call_service_step
    await service_task
  File "/usr/src/homeassistant/homeassistant/core.py", line 1787, in async_call
    task.result()
  File "/usr/src/homeassistant/homeassistant/core.py", line 1824, in _execute_service
    await cast(Callable[[ServiceCall], Awaitable[None]], handler.job.target)(
  File "/usr/src/homeassistant/homeassistant/helpers/entity_component.py", line 213, in handle_service
    await service.entity_service_call(
  File "/usr/src/homeassistant/homeassistant/helpers/service.py", line 680, in entity_service_call
    future.result()  # pop exception if have
  File "/usr/src/homeassistant/homeassistant/helpers/entity.py", line 968, in async_request_call
    await coro
  File "/usr/src/homeassistant/homeassistant/helpers/service.py", line 720, in _handle_entity_call
    await result
  File "/usr/src/homeassistant/homeassistant/components/volumio/media_player.py", line 258, in async_play_media
    await self._volumio.replace_and_play(json.loads(media_id))
  File "/usr/local/lib/python3.10/json/__init__.py", line 346, in loads
    return _default_decoder.decode(s)
  File "/usr/local/lib/python3.10/json/decoder.py", line 337, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/usr/local/lib/python3.10/json/decoder.py", line 355, in raw_decode
    raise JSONDecodeError("Expecting value", s, err.value) from None
json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)

same here. as i know its volumio problem