4.Go to the Mixer Recording page and select “ALT” as the recording source. Click “Reset” to make sure the recording volume is on the default highest level (0dB). This is actually a high-quality onboard loop-back path from the Line-out directly to the Line-In. This allows you to get realistic output and input quality ratings for the Xonar D2X audio card.
4
You may also choose to use an external 3.5mm line cable as follows (as short as possible) to connect the Front-Out jack to the Line-In jack for loop-back testing. In that case, please select “Line In” as the recording source on the mixer page.
3.5mm Line Cable