Jeff, With Vista and the UAA initiative we are taking big steps towards a more transparent audio hardware ecosystem (I am referring to the consumer market here - the 95% case) and through full discoverability of audio device capabilities and the move towards independent devices we hope to create a better user experience in our operating systems of the future for the regular PC user. One important aspect of the usability and discoverability of logical audio devices exposed by an audio adaptor is that they are independent from each other. By this I mean the audio solution has enough [converter] resources to treat each logical input and output device/connector independently. In the cases where multiple audio endpoints connect to a single DAC or ADC resource it is important that the operating system is made aware of this through defined driver OS interfaces so the user can be informed by the OS what device he can expect to be active/operational. In the hardware realm, one of the UAA technologies support the exposure of the system implementers intentions for logical audio device support through a defined firmware method (read about Pin Configuration registers in the HD Audio 1.0 spec or here <http://www.microsoft.com/whdc/device/audio/PinConfig.mspx> if you want to learn more about that). Ideally all inputs and outputs on a PC are wholly independent and the capabilities of the audio device completely discoverable and that is the direction we are driving for Vista and beyond. What we want to enable is total transparency through simple audio path designs in hardware that enable more powerful OS audio policy/troubleshooting features and more flexibility with the use of the audio device for our future OS features and for media applications running on Windows. This is equally true on the input side where when the ADC resources are limited but the number of logical input devices exposed outnumbers the available ADCs. While this in itself is not recommended, the muxed behavior is preferable in the context of predictability and user friendliness. It is hard for a normal user to understand why the integrated microphones on the laptop still are recording after plugging in the headset into the Line/Mic jack on the side for instance. In Vista we discourage the use of mixed input devices sharing one ADC for usability reasons and our operating system will treat these (when exposed by the driver) as muxed devices sharing one ADC. It seems you are missing the ability to expose a multi input mixed device and my question would be, why? What common user scenario is supported by mixing multiple inputs to one ADC? Sincerely, Hakon Strande PM Integrated, Internal, External, and Wireless Audio Devices MediaTech/DMD/Windows Client/Microsoft ________________________________ From: wdmaudiodev-bounce@xxxxxxxxxxxxx [mailto:wdmaudiodev-bounce@xxxxxxxxxxxxx] On Behalf Of Jeff Pages Sent: Sunday, February 19, 2006 4:41 PM To: wdmaudiodev@xxxxxxxxxxxxx Subject: [wdmaudiodev] Audio input summing under Vista With our multichannel sound cards, we have a summing node (KSNODETYPE_SUM) in the input topology so that multiple physical inputs can be summed into a single waveIn device. Under Vista, each input bridge pin creates its own waveIn device, so it would appear that summing multiple inputs to a single device is no longer possible. Is this in fact the case, or is there something I'm missing? Jeff Pages Innes Corporation Pty Ltd