I don't know when this started happening, but there was a time when all audio/video played in my current setup. My computer is a Dell Dimension 3000, XP Pro, 1MB mem, Soundblaster Live 24 bit sound card...your typical Dell setup. I have system sounds. If I go to YouTube, I get video and sound. My kids games all work. However, we noticed that .wmv files e-mailed to us play video and no sound. Then I went and just grabbed an .mp3 file off my hard drive and that doesn't play sound either. I rolled back to WMP10 with no luck. I installed "all-in-one" codecs described in some posts with no luck. I installed the ac3filter guaranteed to work in some threads with no luck. Nothing in muted, unplugged, etc...
Can anyone give me some suggestions to try next? I'm all tapped out....