Uncheck the
Use Left Channel Calibration reference, since you're not using it.
This is explained in the
REW HELP FILES under
Calibrating the soundcard and under
Soundcard connections
You are using the soundcard cal file method of calibration, so you will use the looped cabled during calibration to create your soundcard file and then store it and load it into REW.
Then you'll remove the looped cable and your ready to go and hook up your cables.
With an ECM8000 type cal file, the C-Weight check box doesn't have any effect.
There are some reported problems with that soundcard and VISTA...
brucek