Surveillance cameras disconnect after a day

I am running the surveillance add-on with 10 cameras licensed.  It worked well for quite a while and now the cameras disconnect after a day.   They all don't go at once, 1 or 2 at a time.  I can usually get them running again with the connect button but they will eventually stop again.  This started when I did a factory default on the unit and reinstalled the surveillance app.  Everything else is default without anything else running.