Well I can't reproduce the failure. Can you post the version number that's running on each of the Rokus? Also, those two models are practically identical, so I'm suspecting the problem has to do with the location or network of the Rokus and not the particular models. Is it possible to move the office Roku to your home or vice versa to test whether the failure follows the Roku or the location? Finally, can you PM me the serial number of the failing unit and the date, time and time zone when one of the failures happened?
--Mark