Thanks for the reply.
Yes I am using EXCL NVIDIA High Definition Audio inside REW on the output.
And I am always disable the enhancements in the Enhancements tab, so that one is ticked.
And my Supported Formats tab is
Channels: 8
HDCP: Supported
16 Bit and 24 Bit
32,0 Khz, 44,1 Khz, 48,0 Khz...