Step 1 Click the "Start" button in the lower left side and then click the "Control Panel" button to open the "Control Panel" window.
Step 2 Click "Category" in the upper right side and select "Small icons" and then the control panel will be shown as the following:
Step 3 Double click to open the "Sound" window and select the "Recording" tab.
If there is no "Stereo Mix" in the program list, please right click the list and select "Show Disabled Devices".
If the "Stereo Mix" option still can't be listed, it proves that there is no proper sound card driver installed on your computer, and please check your sound card model and install the correct driver.
Step 4 Right click "Stereo Mix" and then select "Enable".
Step 5 Right click "Stereo Mix" again and then select "Set as Default Device". Then you can capture the sound with Stream-Cloner successfully.