Laptop Sound Problem
 

I have an IBM thinkpad and have had it for about 3 years. THe OS is Windows 98se. The problem is the sound has never really worked. I'll get a crackle and the modem dial-up sound works. I have tried installing the drivers several times and that isn't the problem. I am guessing the actuall sound card is the problem, if so does anyone have any suggestions how I can diagnoss the problem or replace the card. Any help is appreciated.