Great question. And I think you may have helped me solve this issue.
Apparently, both the Ethernet as well Wifi interfaces on the ROCK were enabled. I had previously tested Wifi connectivity and disabled it (or so I thought) – and the time-out issues were due to Wifi interface being active vs. ethernet. I have now disabled Wifi and testing.
So, far so good (crossing fingers)
Didn’t think to go into the Web UI until your suggestion.