Then there is a good indication that your sound card went bad if you have replaced the drivers and all. One thing you might try is to down load a codec pack.
I use and recommend that you use the K-Lite codec pack. This will install complete video and audio codecs that will cover just about all formats. The full version has media player classic ...a free standing media player with no resource hogging at all that is capable of playing audio and video including DVD.
Free-Codecs.com : Download K-Lite Codec Pack 4.8.5 FULL, K-Lite Codec Pack 4.8.5 STANDARD, K-Lite Codec Pack 4.8.5 BASIC : K-Lite Codec Pack is a collection of codecs and related tools