Many thanks for the reply. I will explain my problem further:
I am looking to play tracks of differing quality using WASAPI (exclusive mode):
BassWasapi.BASS_WASAPI_Init(index, 96000, 0, BASSWASAPIInit.BASS_WASAPI_EXCLUSIVE, 0.4F, 0.0F, _wasapiProc, IntPtr.Zero)
At the minute I can use BASS_WASAPI_Init to init to a frequency of 96kh, so far, so good, the 96kh tracks play fine. The problem is with the tracks at 44kh, they are still coming out on my DAC at 96kh.
The question is how do I set basswasapi to correctly output at the correct frequency for the lower quality tracks?