odd lock-up Connect r16.2

Just a few times, I'm getting an odd fail condition, various files. Anywhere I click I get no response other than Windows audible "invalid" audio. Right click in the task bar, ask to close Microstation, no audible, but completely ignores the Close Program request. Must got to Task Manager to and End Task. After closing, re-open file, no ill affects.

10.16.02.34, Windows 10 Pro