It seems like to be something related with desktop themes. I had same problem. But if I create a new desktop account and login, no errors are shown.
I switch to the error account and changed theme to ubuntu default theme. Now all works perfectly. I was working around sounds too. -- gnome-settings-daemon crashes at login https://launchpad.net/bugs/61381 -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs