PKEY_AudioDevice_NeverSetAsDefaultEndpoint

You might decide to set up certain devices so that they can never be selected as default devices. These include, for example, modem lines and medical audio devices.Windows 7 and later versions of Windows provide the PKEY_AudioDevice_NeverSetAsDefaultEndpoint registry key to allow you to prevent the selection of the endpoint of a device as the default endpoint.

The following INF file excerpt shows how to use PKEY_AudioDevice_NeverSetAsDefaultEndpoint to set up an endpoint so that it can never be selected as default.

[Version]
...
Class=MEDIA
ClassGuid={4d36e96c-e325-11ce-bfc1-08002be10318}
...

[USBAudio]
...

[USBAudio.Interfaces]
AddInterface=%KSCATEGORY_AUDIO%,"GLOBAL",USBAudio.Interface
...

[USBAudio.Interface]
AddReg=Xyz.AddReg
...

;; AddReg section to setup endpoint so that
;; it cannot be selected as the default endpoint.
[Xyz.AddReg]
HKR,"EP\\n",%PKEY_AudioEndpoint_Association%,,%KSNODETYPE_GUID%
HKR,"EP\\n",%PKEY_AudioDevice_NeverSetAsDefaultEndpoint%,0x00010001,NeverSetAsDefaultEndpointMaskValue
...

[Strings]
KSCATEGORY_AUDIO="{6994AD04-93EF-11D0-A3CC-00A0C9223196}"
PKEY_AudioEndpoint_Association="{1DA5D803-D492-4EDD-8C23-E0C0FFEE7F0E},2"
PKEY_AudioDevice_NeverSetAsDefaultEndpoint = "{F3E80BEF-1723-4FF2-BCC4-7F83DC5E46D4},3"
...

In the preceding example, NeverSetAsDefaultEndpointMaskValue represents a DWORD mask value that is a combination of device role flags and data flow flags.

The following INF file snippet shows how an undefined output device (KSNODETYPE_OUTPUT_UNDEFINED) is set up so that its endpoint is never selected as default, regardless of the device role and the data flow direction.

[Version]
...
Class=MEDIA
ClassGuid={4d36e96c-e325-11ce-bfc1-08002be10318}
...

[USBAudio]
...

[USBAudio.Interfaces]
AddInterface=%KSCATEGORY_AUDIO%,"GLOBAL",USBAudio.Interface
...

[USBAudio.Interface]
AddReg=MDVAD.EPProperties.AddReg
...

;; AddReg section to setup endpoint so that
;; it cannot be selected as the default endpoint.
[MDVAD.EPProperties.AddReg]
HKR,"EP\\0",%PKEY_AudioEndpoint_Association%,,%KSNODETYPE_OUTPUT_UNDEFINED%
HKR,"EP\\0",%PKEY_AudioDevice_NeverSetAsDefaultEndpoint%,0x00010001,0x00000305
...

[Strings]
KSCATEGORY_AUDIO="{6994AD04-93EF-11D0-A3CC-00A0C9223196}"
KSNODETYPE_OUTPUT_UNDEFINED="{DFF21CE0-F70F-11D0-B917-00A0C9223196}"
PKEY_AudioEndpoint_Association="{1DA5D803-D492-4EDD-8C23-E0C0FFEE7F0E},2"
PKEY_AudioDevice_NeverSetAsDefaultEndpoint = "{F3E80BEF-1723-4FF2-BCC4-7F83DC5E46D4},3"

In the preceding example, 0x00000305 is the bitwise OR combination of all the flags and masks available for PKEY_AudioDevice_NeverSetAsDefaultEndpoint. The following table shows the flags and masks and their values.