Traceback (most recent call last):
  File "/usr/bin/ubuntuone-preferences", line 599, in __handle_response
    self.devices.handle_bw_controls_changed()
  File "/usr/bin/ubuntuone-preferences", line 251, in handle_bw_controls_changed
    self.bw_limited = self.bw_chk.get_active()
AttributeError: 'NoneType' object has no attribute 'get_active'