It's a wonder you haven't given up yet.
Remove and re-install the device in Device Manager.
Then after a reboot, before you mess with sound, go START-RUN-scanregw, which is suppossed to be active in MSCONFIG-STARTUP. "no errors", "do you want to back up again?"...yes.
Actually you could really use Norton Utilities 2002, cheap on ebay. WinDoctor will fix all Active Xcom entries. I use to have to clean reinstall W98SE without this. Thank you Peter Norton.