Comment 13 for bug 873600

Thanks Mikko, it seems your gnome-settings-daemon has an issue, you should open a bug about that:

"(gnome-settings-daemon:1800): Gdk-WARNING **: The program 'gnome-settings-daemon' received an X Window System error.
This probably reflects a bug in the program.
The error was 'BadMatch (invalid parameter attributes)'.
  (Details: serial 525 error_code 8 request_code 143 minor_code 22)
  (Note to programmers: normally, X errors are reported asynchronously;
   that is, you will receive the error a while after causing it.
   To debug your program, run it with the --sync command line
   option to change this behavior. You can then get a meaningful
   backtrace from your debugger if you break on the gdk_x_error() function.)"

do you use a NX config?