my laptop plays no sound, and i didn't know what was wrong until spotify said there was a problem with my sound card. should i get a new one then? how would i go about it? should i buy it and take it to a repair person, or just turn up to pc world and hope for the best? or, could i do it myself? also, how much am i looking to spend? my laptop is about 3 years old, sony vaio vgn-n31s if that helps

thanks