I have an AC1200 powerline network set up.  It seems to be working ok, but when I plugged a home alarm gateway into it, after it was working fine for around 2 weeks, yesterday the gateway started going off-line and on to cellular backup at random times ranging from 20 minutes to a couple of hours.  The weird part was that the gateway would stay off-line for exactly 6 minutes and then go back on-line without any intervention on my part.  I'm trying to figure out if it's a problem with the gateway or the powerline network. Anyone know if there are settings I could tweak on the powerline network to fix this, assuming the problem is with the powerline?