I only have four button blocks that work from one hub (each hub can control 8 units) and no problems. Setup was very easy, I don't know why some reviewers say it's a very difficult setup, I had no problems at all. The only potential issue I came across was that when you add new buttons (a new separate block of 4 buttons) to an already configured hub, you might need to re-enable the skill in Alexa if you configured everything but the Alexa -Procedure for This button does not start, which fixes the problem. The only change I'd like to see is that Alexa can see them as buttons and not motion sensors, so one button could be used as a power button. Currently you have to assign one button as on and another as off (or one button as an on then off delay), but pretty sure it's an Alexa issue and not a broadband connection. Compared to $80 or more for other smart buttons, I really like them.
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