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Read more: https://developer.chrome.com/blog/autoplay/
Browser workarounds
Following workarounds may help with the problem.
Chrome
First, open Chrome menu from top right corner
Check if your Chrome is Managed by your organization at bottom of the menu:
Open Settings
In Settings, select Privacy and security
Select Site settings
Expand Additional content settings at bottom
Select Sound
Add your url with the Voice for Browser into list of sites that are Allowed to play sound
Restart your Chrome
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