Banners with sound

I think most of you experienced these horrible internet banners. And if you didn't, you're a very lucky person.

Just imagine yourself browsing on some websites, and then all of the sudden you hear loud music and/or sound effects coming from nowhere. High chances are that there is an advertisement somewhere with auto-playing sound on the page you're currently checking out.
For some reason people thought it was a good idea to keep the sound of these banners toggled on, meaning that while you watch a clip, write a comment, look at a picture or are just listening to your own music, you suddenly hear this loud noise, ruining whatever you were doing at that moment.

For websites that host copyrighted movies and TV shows, I can understand, but even regular sites have this problem. Deviantart, for instance.
I don't think sites like these should even have this kind of advertisement, next to the fact I think internet banners should shut up altogether.