Hideout: Failed to join any instances

A few times a day I can't return from maps to my hideout, with the error "Failed to join instance because: Disconnected from server."

The map instance still works fine, chat's still working, but I just can't return from it whitout exiting to the character selection screen or relogging. When I relog, all map portals are gone -- like it's a fresh instance. I don't have a reliable way to reproduce this, but it happens a few times each day.