7.1 help

I had installed 7.1 on my pc. during the setup, my mic would not work. setup videos recommended to uninstall and reinstall the 7.1. I am not sure what I did, but I now do not have the 7.1 dropdowns when I am selecting a sound option. I had tried to reinstall the 7.1 application and it still didn't put the dropdown in. I am not sure what to do now please help