The Gorse Fox is vindicated.
Old Bill knocked on the door with Bose in hand. A few minutes later it was plugged in and connected to the Echo Dot. A couple of false starts, but then the music came through and Alexa was able to pump Amazon Prime Music (Unlimited) through the Bose speaker system. Old Bill was happy. All he needs now is an Echo Dot - but that is on his Christmas wishlist.