How do I get fraps to ONLY record INGAME audio NOTHING else

Use MSI afterburner (http://event.msi.com/vga/afterburner/download.htm) to record in the lowest resolution possible (put minimal stress on your HDD), and get something like Format Factory (http://www.pcfreetime.com/download.html) to convert to video to a MP3 file.
You can use Fraps as well, but it put way too stress on your HDD, and will get glitched sound recording as well as give you insane amount of lag.

Option 2: Get a sound recording software (eg. audacity) and set it to record your speaker while

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