Hi @galgalesh - sorry, I just noticed that I never replied here once I solved the issue.
What I did was to ship an own instance of speech-dispatcher directly in the snap and starting it via a special launcher script. This approach is possible in my case since we need a launcher script anyways, so no additional “overhead” needed to be added. Since I also know how the TTS stuff of the application is implemented, I know which packages to ship, so I didn’t need to worry about the whole interfaces and just need the audio-playback plugin.
This is how I did it:
Initially, I tried to hook up the snap to the host systems speechd service, but we can’t guarantee that every system have this installed.
In my opinion, having speechd available as a snap interface would be pretty neat.