Since these drivers are unsigned or for older Windows versions, you may need to install them manually: the 64-bit Windows 10 driver (ZIP or EXE).

Navigate to your extracted folder and select the cmi8738.inf file (sometimes it is cmi8338.inf if it’s a variant). Click Open .

The CMI8738 (C-Media) is a legacy audio codec commonly found on older motherboards and PCI/PCIe sound cards. Official driver support for newer Windows versions is limited; Windows 11 may not include fully compatible built-in drivers for 64-bit systems, so you may need specific drivers or workarounds to restore full audio functionality (jack sensing, multi-channel, low-latency playback).

The (often labeled as C-Media CMI8738/C3DX PCI Audio Device) is a legacy PCI sound card chip that was popular in the late 1990s and early 2000s. Because this hardware is so old, C-Media (the manufacturer) has not released a dedicated driver specifically designed for Windows 11.