So I recorded audio & video with my computer ( NVidia Geforce instant replay ) of my mom singing a very deep song, completely out of her head with the guitar. I really want to save what she sang, but the problem is, the system audio that I had on almost completely blocks out what she was singing. I need to somehow remove the recorded system audio from the file and only leave the microphone's audio.. Is there any possibility to do this?
Sadly no, unless it is only on one track and you can remove it, or if your audio is on one track and system audio is on both left and right (you may be able to invert and cancel out the system audio), or if the system audio is at one frequency that you can EQ out.
Basically, once you have recorded audio, it is very difficult or impossible to remove sounds from that recording to leave your desired sounds.