SourceOne Offline Access (v6.7 SP2) Item Retrieval Looping

We recently migrated (about 4 months ago) from EmailXtender 4.8 to SourceOne 6.7 SP2.

We have a mixture of Desktop PCs and Laptops (with a mixture of Outlook 2003 and 2010) scattered around the country and with EmailXtender the Desktops were always configured with the Legato EmailXtender Shortcut Add-in for Outlook so always retrieved shortcutted messages direct from the server and never cached any messages locally, and the Laptops had the SourceOne Offline Access client (or equivilent EmailXtender User Cache as it was previous).

After migrating to SourceOne we installed the SourceOne Offline Access client on both Desktop and Laptops and up until recently they've all been configured to cache all items in the users mailbox.  This has been working fine except the amount of data synchronising from the backfill server to the local caches is extremely large each day and tends to max out some of the sites WAN connections for a considerable part of the day.

As most of our desktop users rarely retrieve older messages that are shortcut (the policy shortcuts after 28 days) I decided to reconfigure the Desktop machines that are always going to be on the network therefor have direct access to the SourceOne Server, so that they do not cache any items locally so old messages are retrieved direct from the servers store.

I changed the "Cache items that" setting to "Don't cache any items" in the Outlook SourceOne "Cache Settings" options so that nothing is cached, tested the settings and it works ok.  No items are cached and everything is retrieved successfully from the server OK.

However, on a few of the Desktops (all Windows 7 with Outlook 2010) that the "Don't cache any items" is set I have an issue where the SourceOne Offline Access item retrieval screen pops up randomly and starts to retrieve messages and will not stop until both the Outlook.exe and ExOAAgent.exe processes have been terminated.  The user had not clicked on a message to initiate the request and it appears that it is looping throught the users entire mailbox and retrieving messages one at a time.  It doesn't always happen wien Outlook is being used, Outlook can be minimised and they are using another applciation and it occurs.

I get reports of this happening 5 or 6 times per day from each of the users it affects and the only way round it is to kill Outlook and ExOAAgent.

Has anyone else seen this issue?

Thanks.