Are you using Sonos Voice Control (SVC) or Alexa? If so, one or both may be the issue as they can both be activated simultaneously on the Era series. Sometimes a voice assistant will pick up a conversation sound and think it’s a command to play. My Era 300’s with SVC are sometimes prone to start playing without a direct command. The oddity may just be inherent to voice assistants in general; but can be annoying.
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