Loop-back measurement procedure

Select Measurement->Test Current Levels to display the dialog box showing the input and output levels. If your sound card supports the WinMLS mixer, the volume controls Sync. Out and Sync. Input will be displayed as shown to the right in the figure below. Use these controls to set the volume of the loop-back synchronization signal.

Select Measurement->Start Measurement to start the measurement. An error message will be given if the loop-back volume is too low or too high.

The result of a successful measurement will now have almost the correct initial time delay. But as we have seen, the sound card has a delay of some samples, which is usually less than 1 millisecond. To subtract this delay a measurement system correction of the sound card must be performed as described in the FAQ.