Yes, even if you don't use the "wake" word "Alexa." Actually, it may happen—it does to me often—that Alexa turns on and starts speaking to you even if you didn't solicit her. The current standard for an Alexa-powered device to obtain an Alexa certification is set to a maximum of three false alarms per day, which means that situations, where Alexa listens without the user invoking one of the wake words (Alexa, Echo or computer), are far from rare. This ensures that no private conversations are sent to the cloud, even in the case of wake word false positives." Crowdsourcing voice samples instead of secretly eavesdropping on user conversationsIn the Alexa app, Amazon says that this secret eavesdropping setting which it calls "voice recordings" can be disabled.

Source: Forbes May 16, 2019 06:33 UTC