I did as described by Tokyobadger https://ubuntuforums.org/archive/index.php/t-2347827.html on 18may2017, and the problem has vanished unti now (12jun2017).
I did as described by Tokyobadger https:/ /ubuntuforums. org/archive/ index.php/ t-2347827. html on 18may2017, and the problem has vanished unti now (12jun2017).