Sound issues..

'Evening, everyone..
There's something wrong with the sound on my computer. When it comes through the speakers, it's all distorted and sounds like its underwater, echoey and stuff. Same goes for the headphones. Any idea what it is? I opened her up and dusted off the sound card and that didn't work.
Any suggestions?
Thanks
James
There's something wrong with the sound on my computer. When it comes through the speakers, it's all distorted and sounds like its underwater, echoey and stuff. Same goes for the headphones. Any idea what it is? I opened her up and dusted off the sound card and that didn't work.
Any suggestions?
Thanks
James