Thanks Matthew. that what I'm looking for.I'm developing chat application which can mute all other sound when the call comes in. We have external device which connected through line in where the voice from callee will channel hear.BTW, was there any API those can configure to listen the line in. I was trying manually set the listen checkbox inside the listen tab on line in properties. Any way we can set it programmatically. Regards Muhammad Firdaus b. Abu Bakar ________________________________ From: Matthew van Eerde <mateer@xxxxxxxxxxxxx> To: "wdmaudiodev@xxxxxxxxxxxxx" <wdmaudiodev@xxxxxxxxxxxxx> Sent: Thu, November 25, 2010 1:09:37 AM Subject: [wdmaudiodev] Re: Win7 mixer Why do you want to mute all other apps but yours? What does your app do? In Windows 7 you can use the "ducking" feature to attenuate (not mute) other apps while allowing your app to remain at full volume http://msdn.microsoft.com/en-us/library/dd940517(VS.85).aspx From:wdmaudiodev-bounce@xxxxxxxxxxxxx [mailto:wdmaudiodev-bounce@xxxxxxxxxxxxx] On Behalf Of FabWar® Sent: Tuesday, November 23, 2010 7:26 PM To: wdmaudiodev@xxxxxxxxxxxxx Subject: [wdmaudiodev] Re: Win7 mixer Thanks Matthew , BTW, if I used (IAudioEndpointVolume::SetMute) to mute all application was it mute the master volume. My purpose to mute all application instead of my application Regards, Muhammad Firdaus B. Abu Bakar Regards Muhammad Firdaus b. Abu Bakar ________________________________ From:Matthew van Eerde <mateer@xxxxxxxxxxxxx> To: "wdmaudiodev@xxxxxxxxxxxxx" <wdmaudiodev@xxxxxxxxxxxxx> Sent: Wed, November 24, 2010 12:24:10 AM Subject: [wdmaudiodev] Re: Win7 mixer You can mute your own application's sounds (ISimpleAudioVolume::SetMute), and you can mute the audio device (IAudioEndpointVolume::SetMute) which effectively mutes all applications, but you can't mute or unmute other applications that are not yours. From:wdmaudiodev-bounce@xxxxxxxxxxxxx [mailto:wdmaudiodev-bounce@xxxxxxxxxxxxx] On Behalf Of FabWar® Sent: Monday, November 22, 2010 6:07 PM To: wdmaudiodev@xxxxxxxxxxxxx Subject: [wdmaudiodev] Win7 mixer Hye all, Is there anyway we can do remote control each of mixer from application in win7. Controling for muting and unmuting Regards, Muhammad Firdaus B. Abu Bakar Regards Muhammad Firdaus b. Abu Bakar Regards Muhammad Firdaus b. Abu Bakar