How to use a multi-room group name in a command

[xFlip]

I have a multi-room group called "downstairs". Alexa struggles to recognise anything I say to refer to the group. 

Should Alexa recognise the following?  Which does Alexa recognize most readily?

(1) "Alexa, play White Christmas on downstairs"
(2) "Alexa, play White Christmas on downstairs group"
(3) "Alexa, play White Christmas on the downstairs group"
(4) "Alexa, play White Christmas on the group called downstairs"
(5) "Alexa, on downstairs play White Christmas"

Any others?