Even if that is possible, modern browsers are slowly implementing features that prevent videos from automatically playing, so it's not too far-fetched to consider that they might also be preventing audio from automatically playing.
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Are you building a mobile app like a game or are you building a website?
Autoplay of sound on websites is not supported by all browsers and mobile devices. Many people prefer to block autoplay through their settings or via external add-ons. Either way, you can't be sure autoplay will work for everyone. For best results, use an audio player with controls.