I had a motherboard with built in sound - but the sound did not work. Neither did it work in Windows. So I bought a separate sound card that did work right away. In both Windows and LinuxMint.
Now it does not work in LinuxMint any more. Once it didn't work and I was able to change some settings to get it to work. Not any more.
In sound settings box, I have set this card to be the player for sound events, music and audio. There is a test button there and when I press that - there is sound. Some loud beep. But in Totem or Kaffeine - nothing.