Looks good… You must be close…
I have Microsoft David as well, I just ticked the box to play the audio when not in focus.
The key is the next line after the one you highlighted, that is if its a STRING, then it will be read aloud.
Test it with this flow;
[{"id":"1c361989.59fc06","type":"ui_audio","z":"f73f253c.88dd6","name":"","group":"fcb8bf11.614a4","voice":"en-US","always":true,"x":740,"y":520,"wires":[]},{"id":"40efb4e5.fe7dcc","type":"inject","z":"f73f253c.88dd6","name":"","topic":"","payload":"hello world 1 plus 1","payloadType":"str","repeat":"5","crontab":"","once":false,"onceDelay":0.1,"x":520,"y":560,"wires":[["1c361989.59fc06"]]},{"id":"fcb8bf11.614a4","type":"ui_group","z":"","name":"Default","tab":"39d04cf4.60bb0c","disp":true,"width":"6","collapse":false},{"id":"39d04cf4.60bb0c","type":"ui_tab","z":"","name":"Home","icon":"dashboard","disabled":false,"hidden":false}]
I know this speaks once every 5 seconds.
And yes, it will be a very plain looking dashboard, that’s fine, we don’t need anything fancy because it will not be in view anyway.