Could you try if https://launchpad.net/ubuntu/+source/ubuntu-system-settings/0.3+15.04.20150127.1-0ubuntu1 fixes the issue for you?
Could you try if https:/ /launchpad. net/ubuntu/ +source/ ubuntu- system- settings/ 0.3+15. 04.20150127. 1-0ubuntu1 fixes the issue for you?