I hear echo sound every time i play music/movie and i cant figure out to turn it off "how"
Does it happen with headphones in as well? If not, do you have a built-in-microphone? Sometimes the sound coming of the speakers can be picked up by the microphone, resulting in an echo sound. Make sure that the microphone is off (or test it by covering it up while playing some music), and quit out of any applications that are using it.
If you hear it in the headphones as well, it could be a sound card problem, which means it would need replacing. If you don't hear it in the headphones, but hear it in the speakers and don't have a mic, it's either your speakers, or (more likely) your computer just doesn't get along with whatever software you're using to play movies/music.