Hi guys, I would like to activate the multi-channel volume control (As described in the DDK article "Exposing Multichannel Nodes"). Unfortunately, I was not yet been able to do it, even though I have followed the instructions as much as I could. Hopefully, someone here has done it before. The article describes a way to report the number of channels through a BASICSUPPORT query on a given node. In AVStream drivers, the system takes care of reporting this information based on some static data structures, so AVStream drivers do not need to actively report BASICSUPPORT queries. So I have included the following structures to my driver (see code at the bottom). However, even though I have specified 4 channels in the structure, the volume control still only has 2 channels. I have also tried specifying Stepping Ranges like the example does, but it did not make a difference. I'm pretty sure one of you has done this kind of thing before. What am I doing wrong? Anything specific to AVStream? Any reply would be appreciated, even if it's short. Mathieu Routhier //----------------------------- static const KSPROPERTY_MEMBERSLIST ksPlaybackVolumeNodeMembersList[]= { {//KSPROPERTY_MEMBERSLIST {//KSPROPERTY_MEMBERSHEADER MembersHeader; 0,//ULONG MembersFlags; 0,//ULONG MembersSize; 4,//ULONG MembersCount; KSPROPERTY_MEMBER_FLAG_BASICSUPPORT_MULTICHANNEL //ULONG Flags; }, NULL //const VOID* Members; } }; static KSPROPERTY_VALUES ksPlaybackVolumeNodeValues= { {//KSIDENTIFIER PropTypeSet; STATICGUIDOF(KSPROPSETID_Audio),// GUID Set; KSPROPERTY_AUDIO_VOLUMELEVEL, // ULONG Id; 0 // ULONG Flags; }, SIZEOF_ARRAY(ksPlaybackVolumeNodeMembersList), //ULONG MembersListCount; ksPlaybackVolumeNodeMembersList //const KSPROPERTY_MEMBERSLIST* MembersList; }; static KSPROPERTY_ITEM ksVolumeNodeAudioPropertyItems[]= { {//KSPROPERTY_ITEM KSPROPERTY_AUDIO_VOLUMELEVEL, //ULONG PropertyId; GetPlaybackVolume, //PFNKSHANDLER GetPropertyHandler; sizeof(KSNODEPROPERTY_AUDIO_CHANNEL), //ULONG MinProperty; sizeof(LONG), //ULONG MinData; SetPlaybackVolume,//PFNKSHANDLER SetPropertyHandler; &ksPlaybackVolumeNodeValues, //const KSPROPERTY_VALUES*Values; 0, //ULONG RelationsCount; 0, //const KSPROPERTY* Relations; MySupportHandler, //PFNKSHANDLER SupportHandler; sizeof(LONG) //ULONG SerializedSize; } }; ****************** 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.de/