When i play music or a movie the sound echos itself from speaker to speaker the delay is ussually around a half of a second. How can i Fix this?

First disconnect the battery then wait ten secondsand reconnect this should reset your radio and other electronocs in the car

It might still be a installation issue but if you are using a Surround Sound type amp that might be on. If the unit is doing it by itself then there could be an internal problem with a delay line or A/D converter.
In all of my years I have never heard of this symptom though.

Try resetting it:
Link to Manual

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.

First Check for the cable or your players grounding/shielf wire.

Echo is caused by a number of variables. Are you in a large room with mic extended away from you? Mic too far away will create echo. Also try turning down the gain for the mic

I had this problem for months - I finally figured it out on my own...

Go to your RealTek HD Audio Manager (this is either a red speaker icon in the bottom right hand corner or if you go to 'control panel, sounds speak and audio devices, realtek hd sound effect manager)

once you have the window open, under 'sound effect, go to environment and to the right of the drop down menu, click 'RESET'.

After months of trying to fix this issue, this fixed it for me!!! I hope it does for you too!

The echo you hear is the audio delay between your TV speakers and Bose speakers. Muting (or lowering the volume) on the TV will eliminate the echo. Some TVs have a setting to turn of TV speakers entirely, allowing you to listen to your TVs audio strictly through your Bose system.

I found that the best way to avoid this problem is to mute the television speakers or, if you can, turn off the speakers. There seems to be a very brief delay between TV and theater speakers, causing what sounds like an echo. hope this helps.

You want to adjust the "DELAY" setting on the receiver. The standard (default) delay setting is 20mS, which may need to be shortened if your speakers are well behind your listening position. In a proper setup, you should not detect a significant echo effect in surround programming (unless it is a purposely "echoey" scene). Also, make sure you don't have any of the "enhanced" DSP modes engaged -- some of these are quite echoey. if it has speaker set up, there should be a setting for distance. You might have it set close, so that by the time you hear the fronts, the rears should go. Try setting it farther each time until it sounds right. good luck