Great,
And have a look at Universal Media Player - A Generic storages place for your Homey, speakers, tv’s or other media devices - Apps - Homey Community Forum (athom.com)
Is uses the same mecanics (Start condition/action and then a Url trigger) to play sounds from a UPnP (sometimes “called” dnla) device (most/alott-of routers/wifi have the ability for that) on devices.
Use it as a condition card (and set the delay correct in the devices (also in TTS device=check settings)) and it waits for the sound to finish playing before it sends the speech.
That way you get a real got announcement system ( How to make a Great Public Announcement (PA) System with any device! - Apps - Homey Community Forum (athom.com))
I am working on an App that wil make device-states (turning them on-off and reset-variables like volume) easier for the announcement system.