Blank cameras in timeline view.

[Nicholas Odorizzi]

When I click on the timeline view I get random cameras that show black. There are recordings and alerts, so they are recording and working, just in the view they show black. It is pretty random also as to which ones will be black. I have been able to reproduce this with two other machines at different locations. To me this is not a big deal but I have a client that this really annoys. Is there something I am missing or is this just something it does?