I have seen the option of casting an URL to chromecast - but I prefer not to make an webserver for this purpose (and as I know its not possible to make an URL to a place on the Homey device)
So still looking for an more elegant solution. Its supposed to be a smarthome - not solely an advanced home 
Hopefully Homey will support external speakers output natively in not to long time…
By the way: I got to learn that Sonos app has the flow option: «Play a soundboard sound». Too bad Sonos doesnt have smallsized speakers…
