I don't have that version to kick around, so look over http://www.nwlink.com/~zachd/pss/pss.html for clues.
Windows Media Player (WMP) v.7.01003055 no longer plays sound on my PIII Win98 machine. For instance, if I open a sound file (mp3 or a .mpeg movie file with sound) manually, I get the video but no sound. mp3 files play fine in winamp, BTW. I've done two things to troubleshoot: reinstalled WMP and associated various sound files (mp3, etc) with WMP. I have a feeling that a .dll file is missing but I thought completely reinstalling the app would fix this or at least reinstall the correct codecs.