Mic-gain and Speaker-level notifications on Windows XP

[Loren Rogers]

Hey gang,
I've written an application that uses the mixer API for getting/
setting the mic-gain and speaker levels. And I use DirectSound API's
for capturing the mic data and playing back to the speaker. My
question is how can I add "functionality" to Windows XP to know when a
user has adjusted the levels outside of the context of my
application? Windows Vista was easy using IAudioEndpointVolume...
interfaces, but they don't work too well under Windows XP. Thanks in
advance.
/Loren

[Chris P.]

Don't work too well? Hmm, they shouldn't even exist under XP.

To track control value changes on pre-Vista you call mixerOpen with the
CALLBACK_WINDOW flag and a window handle for dwCallback.

Any change made to the controls will send out a MM_MIXM_CONTROL_CHANGE or
MM_MIXM_LINE_CHANGE message.

You will receive messages for all changes including your own, so be careful
you don't get yourself into a loop.

--
http://www.chrisnet.net/code.htm
[MS MVP for DirectShow / MediaFoundation]

[Loren Rogers]

> --http://www.chrisnet.net/code.htm

> [MS MVP for DirectShow / MediaFoundation]

LOL! I was being sarcastic about the Interface not working too well.
Anyway, thank you so much. I'll implement straight away.
/Loren