Welcome to Seven Forums and Happy New Year
Have you tried reinstalling the drivers
for your sound-card? It will help if you could rpovide more details about your hardware including the model, chipset etc?
If i remember correctly, devices marked with an "x" are those that have been disabled - have you tried enabling the device again and letting windows install the driver
Have a look at this SF tutorial - How to Install a Driver in Device Manager
Keep us posted on your progress and regards