Getting electic shock when toucing pc

As the title says I get a ashock when I touch a pc with 1 hand and something else with right hand (something like that)... I left my pc for the night and it worked just fine today, then the sound disappeared, now the sound doesn't work, when I plug in the audio cable from my speakers to the pc, I get weird sounds, even when I just touch almost any part of my pc with it, i still get that sound. Maybe it was overheating and something happenned to my sound card? Any tips/ideas?

I don't even know where this topic should be and I don't know much about comuters so I'm sorry if I didn't give enouth info or something.

If something's wrong with sound card.. what should I be looking at? Would it be possible to fix myself?

Thanks