No, just a fellow X1 and now X2 owner trying to help out. Not being able to create paragraphs here makes it hard to read but I would say rather than both Activities sending the Mute signal it’s more likely one Activity sending it twice for some reason. I have lots of Activities and lots of Devises in each Activity so if it sent every Off sequence my lounge would look like Blackpool illuminations with all the Power toggles turning the equipment and bias lighting Off and On over and over again.