Hello! I'm testing multichannel playback via my PortCls miniport under Windows 7 SP1. Initially, I set an appropriate (6- or 8-channel) shared format for the playback endpoint. After starting 5.1 or 7.1 playback stream (using Foobar2000/WASAPI), I open Windows volume slider by single left-clicking the speaker icon and move the slider related to my driver's endpoint. Stream playback is normal (all channels are played as expected) but Windows mixer sends KSPROPERTY_AUDIO_VOLUMELEVEL requests only for 0/1 channels. If I click the mute icon, KSPROPERTY_AUDIO_MUTE requests are sent only to 0/1 channels too. If I open Windows property applet for the endpoint and switch to Levels tab, I see two sliders: "Line" (name of the corresponding topology filter pin) and "Main volume" (name of the corresponding wave filter pin). If I move the first slider, volume level property requests only for channels 0/1 are sent to my driver (clicking the "Balance" button, I see only two sliders). If I move the second slider on the Levels tab, all 6 or 8 channel volume level requests are sent to my driver. Clicking the "Balance" button, I see 6 or 8 sliders for individual channels, each of them work properly. Opening my topology and wave filters in KS Studio (either from 7.1 or 8.1 WDKs), I see only 0 and 1 channels for KSPROPERTY_AUDIO_VOLUMELEVEL. Descriptor sizes are 152 and 184 for 6 and 8 channels, respectively, but KS Studio does not show remaining channels. My driver exposes multichannel nodes as described here: http://msdn.microsoft.com/en-us/library/windows/hardware/ff536380(v=vs.85).aspx My property handler always sets MembersCount field to the appropriate number of channels, fills the appropriate number of KSPROPERTY_STEPPING_LONG/KSPROPERTY_BOUNDS_LONG descriptors and returns descriptor size 152 for 6 channels or 184 for 8 channels. Why topology nodes are not queried for channels other than 0/1 and system volume slider does not send volume/mute requests for them? Regards, Eugene ****************** 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/