FW: Digital Audio Loop Back deivce/driver

Hello,

I’ve just start working with WDM.
I am trying to implement a virtual audio device and can loop all WaveOut
audio to the WaveIn on a Win XP and 2K OS. Something similar to the VAC
(Virtual Audio Cables).
This is good for recording from other application or playing wave files in
to some application.

I started by taking the MSVAD Simple and replacing the savedata.cpp with my
own loopdata.cpp.
After some playing around it even started to work.

So the questions:

  1. Now I want to have several of these instances in the “Control Panel” ->
    “Sound and Audio Devices” -> Audio tab -> “Sound Playback” and “Sound
    Recording”.
  • What do I need to do?
  • Multiple inf files? Multiple interfaces in the inf file? Couldn’t figure
    that out.
  1. In VAC I think he implemented an upper-layer filter or something like
    that.
  • How do I get started with user-mode drivers/devices?
  • Any reference code for audio user-mode dll?
  • What can it offer me?
  1. If I stick with the WDM MSVAD sample, do I have to get a cat file from
    MHQL for smooth installtion?
  • Is there any way of installing drivers without the cat file and the popup
    warning?

If you have a good reference for a “virtual audio loop device” that has
multiple appearances in the Sound Playback, please email me some
information.

Thank you,
Alex Rosenbaum

SAM - Answering Machine for Skype users
http://www.freewebs.com/skypeansweringmachine/