I am having precisely the same problem. I would say that at least a dozen times a day I lose connectivity to all the devices on my network. I have 4 computers and a wireless printer ... I lose connectivity to everything for about a minute or two and then everything comes back. If I am streaming video on my TV, I get a network error. If I wait a minute and re-establish the connection, everything is okay for an hour or two but then it does it again. I thought that it was a Rouiter problem (and it may be) but when I saw this post I now wonder.
The thing is, it's not just an Internet connectivity issue ... I lose connectivity to everything even on my local network.