Would there be a chance that someone from your household might be messing with you…? I’ve got 4 googles throughout my house, and none of them are acting up. Anyone who has the Home app installed with your household devices listed can use the (hey Google…) Broadcast function when they are not connected to the home wifi to relay messages… I’ve used it multiple times to freak out the kids or ask my partner to call me back when I know she’s likely got her phone on DnD.