Cannot upvote this enough. If the creator of this is listening, for Cthulhu's sake require some input from the user before blaring out sound at them. Was interested, but closed as soon as a tab started making loud noises without me asking it to.
Obviously, I am of the opinion that automatic media playback is a "no no" and I personally dislike the practice. The use of automatic media playback is a red flag in my mind that tells me, "This website is not primarily user-preference driven and is likely something that is about to show me a marketing pitch. The owners of the website do not have a problem with surprising me and/or others nearby due to an oversight or marketing interests."
This thread deserves to be at the top as a reminder to web services and design staff. I realize that decisions for auto-playback likely come from above. If I were in a position of subservience and the directive came from above, I would offer my advice that this behavior is pushy and may turn away users.
I'd appreciate it if web sites asked me before blurting out music - it seems with HTML5 people have forgotten the annoyance of Flash banner ads.