Weird Unifi problem

My Unifi device tracker is working as expected, but I get these error messages every 2 minutes. It started when I moved my unifi controller to another machine. (i’ve changed IP and uninstalled the old one). Any clues what it could be?

HA version: 0.38.2
Unifi controller: 5.4.9


    17-02-14 12:43:11 ERROR (MainThread) [homeassistant.core] Error doing job: Task exception was never retrieved
Traceback (most recent call last):
  File "/usr/lib/python3.5/asyncio/tasks.py", line 241, in _step
    result = coro.throw(exc)
  File "/srv/hass/lib/python3.5/site-packages/homeassistant/components/device_tracker/__init__.py", line 657, in async_device_tracker_scan
    found_devices = yield from scanner.async_scan_devices()
  File "/usr/lib/python3.5/asyncio/futures.py", line 361, in __iter__
    yield self  # This tells Task to wait for completion.
  File "/usr/lib/python3.5/asyncio/tasks.py", line 296, in _wakeup
    future.result()
  File "/usr/lib/python3.5/asyncio/futures.py", line 274, in result
    raise self._exception
  File "/usr/lib/python3.5/concurrent/futures/thread.py", line 55, in run
    result = self.fn(*self.args, **self.kwargs)
  File "/srv/hass/lib/python3.5/site-packages/homeassistant/components/device_tracker/unifi.py", line 83, in scan_devices
    self._update()
  File "/srv/hass/lib/python3.5/site-packages/homeassistant/components/device_tracker/unifi.py", line 74, in _update
    clients = self._controller.get_clients()
  File "/home/hass/.homeassistant/deps/pyunifi/controller.py", line 212, in get_clients
    return self._read(self.api_url + 'stat/sta')
  File "/home/hass/.homeassistant/deps/pyunifi/controller.py", line 118, in _read
    res = self.opener.open(url)
  File "/usr/lib/python3.5/urllib/request.py", line 466, in open
    response = self._open(req, data)
  File "/usr/lib/python3.5/urllib/request.py", line 484, in _open
    '_open', req)
  File "/usr/lib/python3.5/urllib/request.py", line 444, in _call_chain
    result = func(*args)
  File "/usr/lib/python3.5/urllib/request.py", line 1297, in https_open
    context=self._context, check_hostname=self._check_hostname)
  File "/usr/lib/python3.5/urllib/request.py", line 1257, in do_open
    r = h.getresponse()
  File "/usr/lib/python3.5/http/client.py", line 1197, in getresponse
    response.begin()
  File "/usr/lib/python3.5/http/client.py", line 297, in begin
    version, status, reason = self._read_status()
  File "/usr/lib/python3.5/http/client.py", line 266, in _read_status
    raise RemoteDisconnected("Remote end closed connection without"
http.client.RemoteDisconnected: Remote end closed connection without response