Coming from: https://en.community.sonos.com/amazon-alexa-and-sonos-229102/alexa-mic-sensitivity-6798256
I experience the same - even at very low levels I have to go - stand in front of the sonos one and shout alexa for it/them to acknowledge me while at the same time my echo in another room would be able to hear me and respond even if I am not shouting (tested sensitivity while echo was disabled to ensure it was not an issue of alexa diverting to the wrong device).
I tried the mute/unmute mic suggestion which lead to no improvement
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