Recording the sound that is produced by a program is difficult because most sound cards do not support to use their sound output as a sound-input for recording.
However, there is a hardware workaround:
What may work is to connect the "Line-Out"-Jack with the "Line-In"-Jack
of your sound card with a 1:1 connected Stereo cable, possibly with a
galvanic separation device in between.
Please do not connect
"Line-Out" with the "Microphone"-Jack because the microphone outputs a
power-supply for the microphone and if you connect that power-supply
with the Line-Out, you may damage your sound-card. (The "Mic"-jack uses
a Stereo-connector but only supports Mono-microphones. The other channel
is used for the power-supply. )
Hope this helps,
P.S.: Future versions of DemoRecorder may also support direct capturing of sound-output at a software level before it reaches the sound card. As of now I do not know whether this is possible but I must admit that I didn't do extensive research into that direction. What I can tell is that there is no obvious solution for software-based capturing of sound output.
A possible alternative solution would be direct interfacing between your application and DemoRecorder. We provide a custom development service, so you can order some customizations of DemoRecorder which are needed for that purpose.
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