Comment 22 for bug 1248368

Hi, I was suffering from the same problem.
For everybody who ends up here looking for a quick fix, you can manually downgrade the package by downloading it from here (select your platform on the right side of the page below builds):
https://launchpad.net/ubuntu/+source/gnome-settings-daemon/3.4.2-0ubuntu0.6.4

then open a terminal and install it using dpkg (replace the path with the file you downloaded, amd64bit for me):
sudo dpkg -i ~/Downloads/gnome-settings-daemon_3.4.2-0ubuntu0.6.4_amd64.deb