I have Roamio Plus and 3 Mini's. I've found that when I turn the TV off that's connected to my Roamio the Mini looses connection to the Roamio, an error message is displayed. If I go back to the Tivo Menu the Mini is still connected to the Roamio as I can view the recorded shows and watch/stream the Live TV.
I have MoCa bridge set on my Roamio with connection to my LG SmartTV so maybe when the TV turns off it's funkin' up the connection. Anyone else encountering this?