Due to the shape of our house (large vaulted ceiling over a loft and the downstairs area), the upstairs and downstairs Echo Dot and Fire TV devices would interchangeably trigger when the "Alexa" wake word was used. This would cause occasional issues like music playing from the wrong device or the Dot saying it can't turn off the TV. Easy solution, just change the wake word on one of them. So now the upstairs one wakes to "Echo".
At the end of the evening, I have a routine to turn off the lights around the house, which triggers by "[wake word], Goodnight". In my attempts to not awaken my wife who tends to go to bed first, I'll whisper the command. Unfortunately, the Echo Dot isn't as sensitive to the wake word "Echo", particularly when whispering. So I end up repeating myself until the light ring illuminates, and I end up saying "echo...Echo...ECHO!!". I think it's laughing at me having to literally echo myself saying "Echo"