Try the following...
1. Go to "Control Panel".
2. Click on "Sound".
3. Make sure you are on the "Playback" tab.
4. Click on the device you are trying to fix.
5. Now click the "Configure" button and follow the prompts. (Be sure you also click the "Test" button.)
6. Once that is complete, click the "Properties" button.
7. When you are done with your changes, in "Properties", click "Apply" and then "OK".
8. Then click "OK", again, on the main "Sound window".
If the item doesn't show listed there in the "Playback" tab, right click on the white background in that window and make sure the "Show disabled devices" and "Show disconnected devices" have checked boxes next to them.