By the way, Andrew, you mentioned IAudioVolumeLevel so I assume you are using the DeviceTopology API. If you are using the DeviceTopology API for only main volume control, you should instead use the EndpointVolume API http://msdn.microsoft.com/library/en-us/CoreAud/htm/endpointvolumeapi.asp. This will relieve your software from having to analyze different hardware solutions and also take advantage of any software volume control that the audio system might implement on behalf of the hardware. Also, in general we hope very few apps manipulate the endpoint volume levels. If they do, this should be directly tied to UI. Frank Yerrace Microsoft Corporation This posting is provided "AS IS" with no warranties, and confers no rights. -----Original Message----- From: wdmaudiodev-bounce@xxxxxxxxxxxxx [mailto:wdmaudiodev-bounce@xxxxxxxxxxxxx] On Behalf Of Mitchell Rundle Sent: Monday, December 04, 2006 9:51 AM To: wdmaudiodev@xxxxxxxxxxxxx Subject: [wdmaudiodev] Re: Few questions about core Audio APIs in Vista A1. Sorry, but there is no public method for enumerating all of the audio sessions. A2. Most hardware volume controls have .5, 1 or 1.5dB steps. Whether the hardware returns the actual volume level (e.g. -5dB) or the last value set (e.g. -5.02dB) depends on the driver, but in general you should expect that the level will be a multiple of *pfStepping. Regards, Mitch Rundle Microsoft This posting is provided "AS IS" with no warranties, and confers no rights. -----Original Message----- From: wdmaudiodev-bounce@xxxxxxxxxxxxx [mailto:wdmaudiodev-bounce@xxxxxxxxxxxxx] On Behalf Of Andrew Mindrin Sent: Thursday, November 30, 2006 11:09 PM To: wdmaudiodev@xxxxxxxxxxxxx Subject: [wdmaudiodev] Few questions about core Audio APIs in Vista Hi, The questions are: Q1. Enumerating all audio sessions ---------------------------------- I need to enumerate all audio sessions in Vista to take control over them like Sndvol.exe. Is there a way? I need that to create custom volume control software. I've tried to play with WASAPI, but it is possible only to create new session or to open a sessions of current process created by high-level API. Q2. Volume levels in Vista -------------------------- I've noticed that some sound drivers for Vista doesn't support precise volume setup. E.g. with the latest driver from Creative (2.11.0000) when I set volume by using IAudioVolumeLevel::SetLevel to e.g. -5.02 dB and then has read it by using IAudioVolumeLevel::GetLevel, the result is -5 dB instead of -5.02 dB. Is this driver bug or volume level in Vista can be set\read only with a step returned by GetLevelRange method (pfStepping parameter)? If this is not a bug, how to set\read precise levels? Many thanks, Andrew ****************** 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/ ****************** 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/