You can turn the chime off by following these instructions:

https://support.sonos.com/en-us/article/toggle-a-voice-service-s-wake-word-chime-on-or-off

Thank you but my problem is that the chime volume sometimes is shockingly loud. This happens on occasions when Alexa is mistaken in detecting a wake word. When the wake word is legitimate, ie i call Alexa, the chime volume is different and of acceptable volume.

Even if legitimate, or otherwise, perhaps try @GuitarSuperstar’s suggestion and just switch off the chime altogether in the App. The Alexa volume is otherwise linked to the speaker volume. 

Are you suggesting I turn the chime off to find out whether I continue to hear illegitimate, overly loud chimes? If not, what is the point of turning it off? .... Greg 

Because if it still occurs it may possibly rule out the Alexa ‘wake word chime’ being the issue, ? 

I’ve not ever personally noticed the issue and I have the Arc (lounge), Beam (gen2) (dining room) and Beam (gen1) (main bedroom) and they’ve been there since the devices were first launched, but I have the Alexa wake word chime disabled on all three products.

Nothing ventured… etc.