I'm assuming you are concerned with Windows Vista and 7. If we had created a Device Topology<http://msdn.microsoft.com/en-us/library/dd370825(VS.85).aspx> interface for accessing the equalizer then this would have been easier, but we didn't. So you may be interested in reading this MSDN article Using the IKsControl Interface to Access Audio Properties<http://msdn.microsoft.com/en-us/library/dd316787(VS.85).aspx>. Frank Yerrace Microsoft This posting is provided "AS IS" with no warranties, and confers no rights. From: wdmaudiodev-bounce@xxxxxxxxxxxxx [mailto:wdmaudiodev-bounce@xxxxxxxxxxxxx] On Behalf Of Bogdan Sataric Sent: Tuesday, December 15, 2009 6:07 AM To: wdmaudiodev@xxxxxxxxxxxxx Subject: [wdmaudiodev] Audio Mixer control applet I want to develop an Audio Mixer control applet similar to sndvol32.exe that Windows XP exposes for my USB Audio device. The device will use the generic USB audio driver provided by Windows so the idea is to create a GUI for some advanced settings controlled by standard USB Audio Class 1.0. For example, my device supports equalizer building block of a feature unit and I would like to control it via this GUI. I have noticed that USB Audio driver on Win7 sends the requests for Equalizer but there is no GUI allowing to control it in Win7 mixer. Is this possible? Which Windows APIs should I look into? Are there any examples with similar functionality available? Would it be possible to register such application so it is loaded instead of sndvol32.exe or the equivalent on the later OS'? Thanks in advance for the answers. Bogdan Sataric