...snip..
Actually, more correctly, it responds first because the other also wakes but a millisecond behind so it shuts down again immediately. Any chance that's what's happening?
that's a good observation. If I was in the mood to do science, I'd get a blue tooth speaker paired to a smartphone with a recorded command like "Alexa, what time is it"
Set up the speaker in various positions, and use the phone to play it, while I watched the Echo devices closely to see which picks up. Make sure both have the same wake word.
Them experiment with different placement of the speaker and the two Echo devices.
It's possible the sound is getting to the farther echo faster/more clearly due to some unexpected reason.
Or the two Echoes (in my case a Show and an Echo Gen1) run at different speeds and thus the "faster" one gets credit for figuring it out first.
Or the microphones are of differing quality, such that the father unit has "better" mics, so the audio is louder when Amazon analyzes it and presumes the command belongs to it.
Amazon added a feature to account for this very problem, so its not supposed to screw this up so easily.