Is it possible to record sound played on the sound card?

Is it even remotely possible to record sound that is being played on the sound card? Supposedly, I am playing an audio file, what I need is to redirect the output to the disk. DirectShow or might be feasible.

Any help is greatly appreciated, thanks.

Solution

You need to enable audio loopback device, and you will be able to record from in a stadnard way with all the well-known APIs (including DirectShow).

Loopback Recording
Enabling "Stereo Mix" in Vista
Capturing Window's audio in C#

Once enabled, you will see the device on DirectShow apps:

enter image description here