When you setup the Auto Failover did you select 2 Aux connections for your unicast? So make sure you set 1 for your volume replication NICs and one for the the VIP NIC. See if you can ping from both ends to those NICs from each DSS V6 from the Console screen, to do this go to the Console Screen and enter CTRL + ALT + T then select the Ping tool.

Also this video walks you thru the steps as well w/ Unicast.

http://www.open-e.com/service-and-su...ts-and-videos/