If you want to disable the headphone jack on your computer, you may be able to do so if you have a Realtek sound card. A lot of laptops and desktop computers integrate Realtek audio drivers into the motherboard which enables you to disable the headphone jack. This is useful if you have a faulty card that keeps detecting input when no input is selected.
Double-click the RealTek sound icon in the system tray. Click the folder icon under "Device Advanced Settings."
Click "Disable Front Panel Jack Detection."
Click "OK" and then close the RealTek sound device properties window.