I'm also having problems with the single blade I just received restarting every hour. I was having problems with it restarting every 2 minutes at first so I moved it in front of the Watchguard firewall and connected it directly to the Comcast business router instead. That fixed the 2 minute reboots but now it restarts every hour like clockwork.

Right now I've got it using a stratum proxy running on Windows Server 2012. I'm going to try switching to other proxies to see if it's something on the Windows server that is causing an interruption.