Just for info, even with a fourth 6605 with firmware 201305012030 located in another office we have same problem.
I will try to do a WireShark trace with one of theme but it seems that there is a general problem between edge server and 6605...!
Are there any similar cases?
I contacted Xerox, they told me that there is a known issue that they're trying to solve....
Hope they will fix this problem soon as we have only Mac and cannot install XDA Lite...!