Our production system is at version 9230 and single signon works great.
After I upgraded the development system to version 9.3 build 9301 and 9302. Single signon works, but the logon dialog box is displayed for several seconds while getting connected. I have started to re-enter my credentials a few times then realized that I only need to wait a bit.
With SSO enabled, I do not want to see the logon box unless there is a login failure with the logged in user.
Dave