When consumers obtained Google’s Nest Secure IoT devices there was no statement about microphones within the device.
Google announced now the activation of microphones in the product series via a software update, not only proving the existence of the hidden listening device within the product but also the company’s perception about privacy.
archived source: https://wellthissucks.xyz/2019/02/05/google-enables-undocumented-microphones-in-iot-devices-archived-source/