ios微信h5音频audio无法自动播放

<audio preload="preload" controls id="audio" src="audio.mp3" loop></audio>
<video id="video" controls="" preload="none" mediagroup="myVideoGroup" poster="video.png">
      <source id="mp4" src="video.mp4" type="video/mp4">
      <source id="webm" src="video.webm" type="video/webm">
      <source id="ogv" src="video.ogv" type="video/ogg">
      <p>您的浏览器不支持</p>
</video>
<!-- 必须加在微信api资源 -->
<script src="http://res.wx.qq.com/open/js/jweixin-1.0.0.js"></script>
<script>
     //一般情况下，这样就可以自动播放了，但是一些奇葩iPhone机不可以
     document.getElementById(‘car_audio‘).play();
    //必须在微信Weixin JSAPI的WeixinJSBridgeReady才能生效
    document.addEventListener("WeixinJSBridgeReady", function () {
        document.getElementById(‘audio‘).play();
        document.getElementById(‘video‘).play();
    }, false);
</script>

function playAudio() {
    if (setting.autoplay) {
        if (window.WeixinJSBridge) {
            WeixinJSBridge.invoke(‘getNetworkType‘, {}, function (e) {
                audio.play();
            }, false);
        } else {
            document.addEventListener("WeixinJSBridgeReady", function () {
                WeixinJSBridge.invoke(‘getNetworkType‘, {}, function (e) {
                    audio.play();
                });
            }, false);
        }
        audio.play();
    } else {
        audio.pause();
    }
    return false;
}