How to output voice non-blocking without having to wait for runAndWait()

pyttsx3 Version: 2.71 macOS: 10.14.6

I am writing a voice assistant that has to output voice and then immediately has to listen to the user. The assistant is based on Spade which uses Asyncio.

When I output voice using say("sth") and runAndWait() there is quite a long time that I have to wait for runAndWait() to finish (about 1100ms). I would like to be able to output speech and immediately when the output is finished continue to do other things, like listening to what the user says.

When I use startLoop() I can’t continue with anything until I called endLoop() which also delays everything.

I don’t really understand how startLoop(False) would help me. Executing engine.iterate() myself works, and I receive speech output, but there too I don’t know how to continue with other operations after speech output finished

How would I setup pyttsx3 in a way where I can output speech at anytime without a delay afterwards?

I tried to place endLoop() in a separate deamon thread so I don’t need to wait for it to finish. But in this case say() never returns.

Thank you for your help! Here is my code:

output.py

import pyttsx3
from ava.utterance import Utterance
from log import log_output as log
import threading

class Output:
    def __init__(self):
        self.synthesizer = pyttsx3.init(debug=True)
        self.voice = list(filter(lambda sv: ('Tracy' in sv.name),
                                 self.synthesizer.getProperty('voices')))[0]
        self.synthesizer.setProperty('voice', self.voice.id)
        self.synthesizer.setProperty('rate', 175)

        self.setup_callbacks()


    def setup_callbacks(self):
        self.synthesizer.connect('finished-utterance', self.on_finished_utterance)
        self.synthesizer.connect('started-word', self.on_started_word)

    def speak(self, utterance: Utterance):
        self.synthesizer.say(utterance.body, utterance.name)
        self.synthesizer.startLoop()

    def on_finished_utterance(self, name, completed):
        log.debug("END")
        t = threading.Thread(name="ccpyttsx3", target=self.killme, args=(self.synthesizer,))
        t.setDaemon(True)
        t.start()



    def on_started_word(self, name, location, length):
        pass

    def killme(self, synth):
        print("killme")
        synth.endLoop()