Please check your settings in Debut
Open Options by clicking the Options button on the toolbar
On the Devices under Audio, at least one of the following should be selected
Microphone - Select this option to capture sound from a microphone; make sure that the correct device is selected from the drop-down list.
Speakers - Select this option to capture sound produced by other applications.
*Please note that Debut needs to be launched prior to the application that you are recording for this to work properly
Mouse Clicks - Select this option to record a sound when the mouse is clicked.
*The sound is recorded even if no audio device is found in the system.
If you are trying to record sound from streaming video on your computer, you would need to use a stereo mix option (if your sound card supports this).
In most cases, you can connect a male to male 3.5mm stereo cable from the speaker output on the computer to the Line In port.
This will cause the audio to go out through the speaker port, then back in through the line in where it will be recorded.