SSO / Auth Domains not maintaining session

I am setting up an SSO/Auth Domain Multiple Domains config to share access sessions across multiple Virtual Servers and have struck an issue.

 

I am following the details from here: http://support.f5.com/kb/en-us/products/big-ip_apm/manuals/product/apm-sso-config-11-1-0/4.html and http://blog.garraux.net/2013/05/f5-access-policy-manager-multi-domain-sso/, as well as the training material (where I did this in the course and it worked).

 

But what I am finding in my environment (which is 11.4.1HF2) is that when I go to the Primary Auth URI I get in all good, if I go to any of the auth domains then it redirects me to the Auth URI, but this does not see any existing session, and then sends me back to the auth domain, and back to the primary URI in a loop.

 

Am wondering if its related to this Q from a few weeks ago as the session resetting behaviour sounds about right for what is happening - https://devcentral.f5.com/questions/apm-recreating-session-when-user-hits-default-url

 

Anyone seen this or have any good ides