Seems to be related to this bug, the fix posted there (blacklist module 'acer_wmi' fixed the Issue for me.
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/771758
Seems to be related to this bug, the fix posted there (blacklist module 'acer_wmi' fixed the Issue for me.
https:/ /bugs.launchpad .net/ubuntu/ +source/ linux/+ bug/771758