This is from 2018, but presumably they use largely the same method now: https://...

This is from 2018, but presumably they use largely the same method now: https://www.theverge.com/2018/2/2/16965484/amazon-alexa-supe...

To save a click:

> Apparently, the Alexa commercials are intentionally muted in the 3,000Hz to 6,000Hz range of the audio spectrum, which apparently tips off the system that the “Alexa” phrase being spoken isn’t in fact a real command and should be ignored.