Google went some of the way to battling misbehaviour tabs that want to assault your eardrums, but if you're after complete control, it's time to install MuteTab.
MuteTab provides a global look at active tabs that are sounding off, allowing you to shut them all down at once, or individually. It also keeps track of recently noisy tabs, so you can handle those as well.
For those who don't want to hear anything from their browser, ever, automatic muting is supported. Fine-grained control is provided via black and white lists, so you can handle more annoying websites permanently.
Finally, you can bind actions to certain key combinations, giving you shortcuts to MuteTab's functionality at a moment's notice.
With all these options available, MuteTab should be the only extension you need to handle obnoxiously loud websites once and for all.