Let me float an idea based on this study: it doesn't need to listen for more than the wake word (and some variations of same) in order to activate pretty regularly. The study indicates that just watching TV in a room w an echo device will cause it to wake 1-4 times per hour with half of all wakes resulting in at least 4 seconds of recording and virtually all recordings being sent to the cloud for processing. Even absent any "secret wake words" the device activates regularly enough that it will occasionally react to things you say in conversation as though it's secretly listening.
Also, just thinking like someone who is simultaneously evil and competent, if I were building a device like this that listened for secret keywords I wouldn't have it announce the fact that it heard one.
Let me float an idea based on this study: it doesn't need to listen for more than the wake word (and some variations of same) in order to activate pretty regularly. The study indicates that just watching TV in a room w an echo device will cause it to wake 1-4 times per hour with half of all wakes resulting in at least 4 seconds of recording and virtually all recordings being sent to the cloud for processing. Even absent any "secret wake words" the device activates regularly enough that it will occasionally react to things you say in conversation as though it's secretly listening.
Also, just thinking like someone who is simultaneously evil and competent, if I were building a device like this that listened for secret keywords I wouldn't have it announce the fact that it heard one.