Hi @patrick1,
You could be seeing some performance issues due to the scale of the networked storage that is being scanned and synced. When you point odrive al a very large repository it can take quite a bit of time to chug through it and, during that process, you can see some non-responsiveness from the menu.
Is the Drobo connected over a wired or wireless network connection?
You can try using the CLI, which is more basic and less prone to be impacted by the overhead of large-scale operations, to see if it gives you a better idea of activity. Take a look at this post here for more information: How can I use the CLI to check odrive status?