|Microsoft DirectX 9.0|
The Compact method moves the unused portions of on-board sound memory, if any, to a contiguous block so that the largest portion of free memory will be available.
If the method succeeds, the return value is DS_OK.
If the method fails, the return value may be one of the error values shown in the following table.
Sound cards using the PCI bus do not have on-board memory.
The application's device object must have at least the DSSCL_PRIORITY cooperative level. See IDirectSound8::SetCooperativeLevel.
This method will fail if any operations are in progress.
Header: Declared in dsound.h