When assigning ports Graphisoft told us we did not have to assign the discovery port. This is also in the wiki. I haven't re-assigned this port and, fingers crossed, am not having this problem.
Erika
Architect, Consultant
MacBook Pro Retina, 15-inch Yosemite 2.8 GHz Intel Core i7 16 GB 1600 MHz DDR3
Mac OSX 10.11.1
AC5-18
Onuma System
"Implementing Successful Building Information Modeling"