That link is to a Bose Soundbar 500, but regardless, I cannot find anything that mentions issues with Alexa?Have a look here too, as it sounds more like a bose speaker issue.
Troubleshooting
www.bose.co.uk
For Alexa to be faulty, it would have to be faulty in my two Bose devices which is unlikely.Try as you are, if it seems ok, the speaker has bluetooth just use that to connect to your alexa it's how I connect my speakers up. Maybe the alexa in the speaker is faulty.
Also make a support ticket to bose about it.
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