Plex errors at startup

Configuration
1

I’m running Plex on an NVidia Shield. I can see when it’s playing something, but this is my log:

17-04-23 20:17:18 ERROR (Thread-4) [plexapi] http://192.168.1.36:32400: (401) unauthorized
17-04-23 20:17:18 ERROR (MainThread) [homeassistant.components.sensor] Error while setting up platform plex
Traceback (most recent call last):
  File "/home/homeassistant/.homeassistant/deps/plexapi/server.py", line 47, in _connect
    return self.query('/')
  File "/home/homeassistant/.homeassistant/deps/plexapi/server.py", line 110, in query
    raise BadRequest('(%s) %s' % (response.status_code, codename))
plexapi.exceptions.BadRequest: (401) unauthorized

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/srv/homeassistant/lib/python3.4/site-packages/homeassistant/helpers/entity_component.py", line 155, in _async_setup_platform
    entity_platform.schedule_add_entities, discovery_info
  File "/usr/lib/python3.4/asyncio/futures.py", line 388, in __iter__
    yield self  # This tells Task to wait for completion.
  File "/usr/lib/python3.4/asyncio/tasks.py", line 286, in _wakeup
    value = future.result()
  File "/usr/lib/python3.4/asyncio/futures.py", line 277, in result
    raise self._exception
  File "/usr/lib/python3.4/concurrent/futures/thread.py", line 54, in run
    result = self.fn(*self.args, **self.kwargs)
  File "/srv/homeassistant/lib/python3.4/site-packages/homeassistant/components/sensor/plex.py", line 52, in setup_platform
    name, plex_url, plex_user, plex_password, plex_server)])
  File "/srv/homeassistant/lib/python3.4/site-packages/homeassistant/components/sensor/plex.py", line 74, in __init__
    self._server = PlexServer(plex_url)
  File "/home/homeassistant/.homeassistant/deps/plexapi/server.py", line 27, in __init__
    data = self._connect()
  File "/home/homeassistant/.homeassistant/deps/plexapi/server.py", line 50, in _connect
    raise NotFound('No server found at: %s' % self.baseurl)
plexapi.exceptions.NotFound: No server found at: http://192.168.1.36:32400

Can anyone guess what’s wrong? I’ve really tried to find an answer myself, but I can’t find anything quite like this error and I don’t know enough to figure this out.

Also found this error:

17-04-23 20:18:11 WARNING (Thread-9) [netdisco.ssdp] Found malformed XML at http://192.168.1.36:9080: status=ok
2

I run Plex on a Mac and have the same issue during start, which then somehow resolves itself.