The trick is to get the PKEY_AudioDevice_SetupPreferred property set in the endpoint propertystore for the endpoint that you want to be default. 1) Remove the SetupPrefferedAudioDevices registry setting from you INF. It is not precise enough. 2) For the subdevice that you want to be default add the following registry entries: HKR,"EP\\0", %PKEY_AudioEndpoint_Association%,,%KSNODETYPE_SPEAKER% HKR,"EP\\0", %PKEY_AudioDevice_SetupPreferred%, %REG_DWORD%,1 3) add to the strings section of the inf PKEY_AudioEndpoint_Association = "{1DA5D803-D492-4EDD-8C23-E0C0FFEE7F0E},2" PKEY_AudioDevice_SetupPreferred = "{F3E80BEF-1723-4FF2-BCC4-7F83DC5E46D4},1" Regards, Mitch Rundle Microsoft Corporation This posting is provided "as is" with no warrantees, and confers no rights. -----Original Message----- From: wdmaudiodev-bounce@xxxxxxxxxxxxx [mailto:wdmaudiodev-bounce@xxxxxxxxxxxxx] On Behalf Of Jeff Pages Sent: Thursday, November 01, 2007 10:21 PM To: wdmaudiodev@xxxxxxxxxxxxx Subject: [wdmaudiodev] Setting default subdevice in Vista Our driver installs multiple subdevices, each representing a stereo channel on our multichannel cards. On XP it seemed the first channel always became the default device immediately after installation, but on Vista it's rather random - sometimes channel 1 on our card is marked default, other times channel 2 becomes the default. The SetupPreferredAudioDevices INF keyword allows a particular card to assert itself as the default device, but is there any way to do the same thing with individual subdevices on a multichannel card? Jeff Pages Innes Corporation Pty Ltd ****************** WDMAUDIODEV addresses: Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx Subscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=subscribe Unsubscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=unsubscribe Moderator: mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx URL to WDMAUDIODEV page: http://www.wdmaudiodev.com/ ****************** WDMAUDIODEV addresses: Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx Subscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=subscribe Unsubscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=unsubscribe Moderator: mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx URL to WDMAUDIODEV page: http://www.wdmaudiodev.com/