Computer sound issues, x2

Hello. Long time lurker, first time poster.

I have a sound problem with two separate computers.

The first one is my desktop computer at home. A few weeks ago, the sound went weird. At first I noticed it when playing TES: Oblivion, the background dialogue started to echo. Shortly afterwards, all sounds the computer played (mp3s, videos, games) started sounding scratchy/raspy. The computer is fairly new, I got it as a christmas present, and it has an intergrated sound card.

The second is my (mom’s) laptop which I’m using during the weekdays (when I’m away from home at school). It used to have normal sound playback. Then at some point, this could be some months ago, I noticed the sounds were awfully low even with all the settings at their highest. Now I can’t get it to make a sound of any kind, even with speakers or headphones.

Could it be just a matter of getting new sound card drivers? I did try that, but I’m not entirely sure if I found the right ones (and how to do it). I could try and find the names of the sound cards if that helps.