I have had a little problem with Realtek in Windows 8/8.1. I finally uninstalled (not disabled) the sound driver and installed this old one You could try it and see if it works for you? In the event, you van always roll back to the original
http://www.filefactory.com/file/7gj3yyyuo8cp/R292450.exe
fwiw. My principal computers are mostly Dell. What I did, was mad a "Dell Drivers" folder. I then went to the trouble of downloading every driver they offered, first with Windows 7 and subsequently with Windows 8 and 8.1. Now, whenever I do a reinstall, or any other mishap, I select the device option to update the driver and browse my computer, including sub folders. Just point it at that folder and away it goes - done.