Comment 2 for bug 611730

Thank you for reporting this issue. Since this broke when the new kernel was installed, it is probably something in that kernel that caused the hotkey to quit working. Unfortunately, we need some more information to help resolve this issue. Could you please attach as plain text files, not compressed or zipped, the following:

udevadm info --export-db > udev-db.txt
dmesg > dmesg.log
sudo lsinput > lsinput.log
xkbcomp -xkb :0 - > xkbcomp.txt
setxkbmap -print > xkbmap.txt

Thank you for helping improve Ubuntu.