Right-click it > > Browse my computer for drivers .
The most reliable driver is found in the official Apple Boot Camp 5.1.5621 package. Apple Macbook Pro A1278 Audio Driver Windows 10
If you cannot reinstall Windows and need a workaround for UEFI-related audio issues, some users successfully use the OpenCore Legacy Patcher (OCLP) Right-click it > > Browse my computer for drivers
With the correct audio driver, your A1278 will produce crisp, loud sound through its internal speakers, flawless headphone switching, and a fully functional microphone array. Enjoy your revitalized MacBook Pro – now louder than ever on Windows 10. Enjoy your revitalized MacBook Pro – now louder
If the driver is installed but you see a in the headphone jack and have no internal speaker sound:
If you are in Legacy mode but have no sound, follow these steps to get the specific Cirrus Logic drivers needed for the A1278: