前端 js 播放 base64 编码的 mp3，放出来杂音很大，请教是哪里出错了？

后端传来是 base64-encoded 的 mp3 音频的字符串，码率、声道这些信息（ sampleRate 、numChannels 、bitsPerSample 、dataLength ）不知道，直接放在<audio>中播放是正常的：

<audio controls> <source src="data:audio/mpeg;base64, base64-encoded-string" type="audio/mpeg"> </audio> 

重新解码作为 blob 播放，放出来就很多杂音，这中情况是哪里的问题？

<script type="text/Javascript"> const audioCOntext= new (window.AudioContext || window.webkitAudioContext)(); const decoder = new TextDecoder("utf-8"); function base64ToArrayBuffer(base64) { const binary = atob(base64); const len = binary.length; const bytes = new Uint8Array(len); for (let i = 0; i < len; i++) { bytes[i] = binary.charCodeAt(i); } return bytes.buffer; } function playAudioChunk(base64) { const arrayBuffer = base64ToArrayBuffer(base64); audioContext.decodeAudioData(arrayBuffer).then((audioBuffer) => { const source = audioContext.createBufferSource(); source.buffer = audioBuffer; source.connect(audioContext.destination); source.start(0); }).catch((err) => { console.error("Error decoding audio data", err); }); } // ws-connection ... playAudioChunk(base64-encoded-string); </script>