sound from the speakers comes with some kind of echo. WTH is that?

[Lonkut]

A few days ago I turned my comp on and I noticed that the sound from the speakers comes with some kind of echo. Like a large hall type of thing. It has happened to me before but it went away by itself last time but this time is really annoying. What might be the problem? I didn't mess with the sound properties or anything.

 

[Lonkut]

I would really like it if someone has an opinion about it.

 

[skadistic]

Is it onboard sound or a sound card?

My sound has a problem with the volume being 1/2 of what it was. Just happened out of the blue one day.