The AudioScience Surround Sound eXtensions2(SSX2) allow certain AudioScience products to play, record and mix streams with up to 8 channels of PCMaudio. The number of channels may be 1, 2, 4, 6 or 8.

Under Windows, both the WAVE and WDM drivers support SSX2, and it maybe accessed through the HPI, Wave, and DirectSound APIs.Under Linux, SSX2 is available using the HPI interface.

The following link opens a PDF document on SSX2: Surround Sound eXtensions