As the title says, I would like to record the sound internally on a screen recorded video, without having to use my speakers. Then, I would like to replay my recording with my speakers switched on for when I playback the video on my computer and have the sound working by hearing the video that I recorded. Does anyone know what feature does this? If not, do I need get another piece of software involved?
ActivePresenter allows you to record your voice (using Microphone) and system audio (the internal sound) separately or simultaneously.
However, to record system audio, you still need to plug in the audio output device. Then, just uncheck in the Input Devices option in the Record Video Project dialog to record.
For more information, please refer to this tutorial:
After recording, you can insert audio to your video as you wish: