Frequently I open the app and one of the discs is offline. When I go upstairs and check the disc everything is ok as shown with a green led. Is this some kind of a bug? I am very happy with the m9 but

I just bought the M9 plus with three discs. One in the living room one on the first floor and one on the second floor. I am very happy with the product because for the first time I had 100 mb download