Arc and TV remote sync went bad. Lost volume control and could no longer mute. So I Factory reset the Ark but the Ark failed to register with my account. I tried several times with no success. I then noticed that my SonosID was not visible within the app so assumed the Ark didn’t know where to register. I logged out of the app and back in again and then tried the whole process of registering all over, this time it worked with no issues.