(question on why “simple” example provides but doesn’t allow 5.1 and 7.1 selection) Looking into this some more I figured it out- the “simple” example only provides WAVEFORMATEX support, and thus doesn’t support 5.1, 7.1 and more than 16 bits per sample. I’m not sure why they designed the sample to allow you to try to select those options though, just to have them fail. Paul