Mike,
Could you please detail the steps you took (which SmartApps, how they were configured, etc) in as much detail as possible? Specifics like how many speakers are configured, what their model numbers are, how they are configured in terms of arrangement (are any grouped, etc) and how they are configured in SmartThings. (Assume that you will tear this down and I will be setting it up for you; because I basically am going to be doing just that here.)
I was just able to do this with the pre-configured sounds, dogs barking in this case; but I can confirm that custom TTS messages are broken (“cluck cluck bock bock” in this case). I am making sure the that TTS issue is raised and that someone is actually doing something about it.
Thanks,
Donald