Text to speech Autoplay not working, giving not-allowed error in Angular

Question

I'm working on an angular app which basically shown on tv. When there is any notification sent from server, i want to show the notification and read out loud the notification. I am able to show notification and for reading the notification I'm using SpeechSynthesis API sometimes it is working and sometimes it gives me not-allowed error. After doing some browsing I got to know that these are browser restriction policy and we cant bypass. Then I found an article which told to use AudioContext API, but initially it should have some user interaction.

I've also tried using navigator.mediadevices.getusermedia({audio:true})

var constraints = { audio: true } // add video constraints if required

    navigator.mediaDevices.getUserMedia(constraints)
      .then((stream) => {
        const audioContext = new (window.AudioContext)();
        const objectURL = URL.createObjectURL(audioBlob);
        

        const bufferSource = audioContext.createBufferSource();
        fetch(objectURL)
          .then(response => response.arrayBuffer())
          .then(arrayBuffer => audioContext.decodeAudioData(arrayBuffer))
          .then(decodedData => {
            // Assign the decoded audio data to the buffer source node
            bufferSource.buffer = decodedData;

            // Connect the buffer source to the AudioContext's destination (speakers)
            bufferSource.connect(audioContext.destination);

            // Start playback
            bufferSource.start(0);
            audioContext.resume();
          })
          .catch(error => {
            console.error('Error loading or playing audio:', error);
          });
      })

The above code snippet works in some browser in TV after allowing the permission, but not in all.

Can anyone suggest any approach on how to achieve this.

Note: As this app runs in TV, there wont be any user interactions happening.

Ref: https://developer.chrome.com/blog/autoplay/#iframe-delegation

Thank you, Looking forward.