The "CoolStar SST Audio (WDM)" driver likely refers to a specific audio driver associated with the SST (Sound System Technology) used by some audio hardware components, often related to integrated or specialized audio chips in computers or motherboards. WDM stands for Windows Driver Model, which is a standard driver architecture in Windows operating systems.

This driver is usually installed for audio devices that support the SST technology, enabling your system to properly communicate with the audio hardware, deliver sound output, and handle audio input (if applicable). It is commonly used for drivers for integrated sound chips or other audio devices, and the "CoolStar" part could refer to a branding or a particular version of a hardware product that uses this audio technology.