Having the same issue too. Updated firmware and noticed emails were being missed. D1 light stays flashing until I reboot. From what I can tell, it does that when sending an email. I have them doubled to SMS and email, so far I've missed 2 false alarms because of it. I'm testing 10 half/full duplex to see if that's an issue, but my equipment hasn't recorded any errors yet. In the past I noticed a reset of the power worked and it hadn't stayed up for more than 24 hours. Also placing a call to Leviton (firmware bug maybe?). Will post back with results.