title: Invisible SoundCloud iframes
body: <p>On pages containing multiple SoundCloud iframes, a random subset of those iframes appear invisible in both Chrome and Firefox, and instead of containing the normal SoundCloud content they contain the following HTML. The iframes affected often change with each page load, and youtube iframes on the same page are unaffected. Does anyone know the cause and/or a workaround?  </p>
  
  <p>UPDATE: On further examination, this <em>is</em> standard SoundCloud content, except div id="widget" is empty, and a manual iframe reload on an individual iframe forces it visible. Is this maybe a situation where the iframe is first loaded, then the div content is fetched with an XHR, and on a page where the browser is laboring over numerous loads on a congested network some XHR's silently time out? If so SoundCloud, could you increase your XHR timeout?  </p>
  
  <p>UPDATE 2: I tested this some more on 2 separate machines on the same LAN, and it looks like it might be a problem with the current version of the standard Flash plugin (11.5.502.110 on winXP--installed by auto-update Nov.9, about when this started, and 11.2.202 on Ubuntu 12.04--installed today, Nov. 27). The following information should make it reproducible. I get 100% consistent failures in Firefox on both machines, and I can toggle the failures on and off in Chrome (on both machines) by enabling the standard plugin vs. Chrome's own PepperFlash plugin. There are 100% no failures with PepperFlash, but the current version of the PepperFlash player is unusable because of <a href="http://productforums.google.com/forum/#!topic/chrome/LdKbj-prkfc" rel="nofollow">impossibly choppy audio</a>.</p>
  
  <pre><code>&lt;html lang="en"&gt;
      &lt;head&gt;
          &lt;meta charset="UTF-8"&gt; &lt;meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1"&gt; &lt;meta name="viewport" content="width=device-width, minimum-scale=1, maximum-scale=1, user-scalable=no"&gt;
          &lt;title&gt;SoundCloud Widget&lt;/title&gt;
          &lt;base target="_blank"&gt;
          &lt;link rel="stylesheet" href="/player/assets/widget-22748325.css"&gt;
          &lt;script src="/player/assets/widget-ab572693.js"&gt;&lt;/script&gt;
          &lt;script&gt;
              require(["lib/support", "lib/flash-widget"], function(support, flashWidget) {if (support.newWidget) { require(["application"], function(A) {A.start("207ad5d2")}) } else { $(flashWidget.start); }});
          &lt;/script&gt;
      &lt;/head&gt;
      &lt;body class=" hasGoogleVoiceExt"&gt;
          &lt;div id="widget" style="height: 100%;"&gt;&lt;/div&gt;
          &lt;div id="sm2-container" class="high_performance swf_error" style="z-index: 10000;"&gt;&lt;embed name="sm2movie" id="sm2movie" src="/player/assets/swf-8bc33658/soundmanager2_flash9.swf" quality="high" allowscriptaccess="always" bgcolor="#ffffff" pluginspage="www.macromedia.com/go/getflashplayer" title="JS/Flash audio component (SoundManager 2)" type="application/x-shockwave-flash" wmode="transparent" haspriority="true"&gt;&lt;/div&gt;
      &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>