Bose Home Speaker 300 discovered as DLNA "renderer" - now what?

I have several Bose Home Speaker 300s, which were discovered as DLNA Digital Media Renderer. I can intermittently play media to the speaker (only if I go to the device, controls, browse media pick a source and play). I have not been able to get an automation to play to the speaker (trying to have a motion detector trigger a sound file to play on speaker)