Bought 4 EP10s on amazon in March of this year. a few weeks after using them, One randomly shuts off a few times a day, by itself, even after resetting it and re-adding it to my system. Another one started randomly turning off and on several times each hour. Now it just flashes blue and the relay clicks several times per second, even after I unplug the smart plug and replug it. I can't even reset it. Is it safe to assume that I have 2 defective units?