I wouldn't recommend music particularly, mainly because lyrics don't worry about grammar or standard English usage.
If you have the option, change the language when you're watching TV or films. Change it to English, or at least put the English subtitles on.
Another good site is TED. It's full of interesting videos in English. They are good to actually watch and concentrate on, but there's no reason why you shouldn't play them in the background while doing other things. Each one is 15 minutes long, I think.