Is the following terminal descriptor Ok? // bi-direction handset : Terminal Descriptors (60 bytes) 0x0C, 0x24, 0x02, 0x01, 0x01, 0x04, 0x03, 0x01, 0x00, 0x00, 0x00, 0x00, // ID1, Input Terminal, Handset IN 0x0C, 0x24, 0x02, 0x02, 0x01, 0x01, 0x04, 0x01, 0x00, 0x00, 0x00, 0x00, // ID2, Input Terminal, USB streaming IN 0x09, 0x24, 0x03, 0x03, 0x01, 0x04, 0x01, 0x06, 0x00, // ID3, Out Terminal, Handset OUT 0x09, 0x24, 0x03, 0x04, 0x01, 0x01, 0x02, 0x05, 0x00, // ID4, Out Terminal, USB streaming OUT 0x09, 0x24, 0x06, 0x05, 0x01, 0x01, 0x03, 0x00, 0x00, // ID5, Feature Unit, handset IN volume 0x09, 0x24, 0x06, 0x06, 0x02, 0x01, 0x03, 0x00, 0x00, // ID6, Feature Unit, handset OUT volume Also is the document in the following link still valid? http://www.microsoft.com/whdc/system/bus/USB/usbtelephony.mspx Thanks, Mike ----- Original Message ----- From: DJ Sisolak To: wdmaudiodev@xxxxxxxxxxxxx Sent: Tuesday, April 03, 2007 11:01 AM Subject: [wdmaudiodev] Re: Vista default audio The following tables are from the USB Audio 1.0 specification sample in Appendix C. Note that the 0x401 in the table that indicates a Handset can be replaced with any of the values in the sections of the "Universal Serial Bus Device Class Definition for Terminal Types" (Release 1.0) that Richard mentions below: Table C-6: USB Telephone Input Terminal Descriptor (ID2) Offset Field Size Value Description 0 bLength 1 0x0C Size of this descriptor, in bytes. 1 bDescriptorType 1 0x24 CS_INTERFACE 2 bDescriptorSubtype 1 0x02 INPUT_TERMINAL subtype. 3 bTerminalID 1 0x02 ID of this Terminal. 4 wTerminalType 2 0x0401 Terminal is Handset In. 6 bAssocTerminal 1 0x05 Associated with Handset Out Streaming Terminal. 7 bNrChannels 1 0x01 One channel. 8 wChannelConfig 2 0x0000 Mono sets no position bits. 10 iChannelNames 1 0x00 Unused 11 iTerminal 1 0x00 Unused Table C-9: USB Telephone Output Terminal Descriptor (ID5) Offset Field Size Value Description 0 bLength 1 0x0C Size of this descriptor, in bytes. 1 bDescriptorType 1 0x24 CS_INTERFACE 2 bDescriptorSubtype 1 0x03 OUTPUT_TERMINAL subtype. 3 bTerminalID 1 0x05 ID of this Terminal. 4 wTerminalType 2 0x0401 Terminal is Handset In. 6 bAssocTerminal 1 0x01 Associated with Handset In Streaming Terminal. 7 bSourceID 1 0x09 From Handset Selector Unit. 8 iTerminal 1 0x00 Unused From: wdmaudiodev-bounce@xxxxxxxxxxxxx [mailto:wdmaudiodev-bounce@xxxxxxxxxxxxx] On Behalf Of Mike Dey Sent: Tuesday, April 03, 2007 9:52 AM To: wdmaudiodev@xxxxxxxxxxxxx Subject: [wdmaudiodev] Re: Vista default audio Hi Richard, Thanks for your quick response. Can Microsoft provide us a sample terminal descriptor table for USB telephony devices? Thanks! Mike ----- Original Message ----- From: Richard Fricks To: wdmaudiodev@xxxxxxxxxxxxx Sent: Monday, April 02, 2007 11:41 AM Subject: [wdmaudiodev] Re: Vista default audio Hi Mike, We are addressing this problem. For Windows XP, a QFE is being prepared that will prevent this. This fix is currently schedule to be released in the Server beta 3 shipment and for Vista SP1. The USB Audio INF file contains a statement that causes USB Audio devices to become the preferred device. The resolution involves detecting if this is a telephony device and if so, we will not set it as the preferred audio device. To be considered a telephony device, it must describe itself to the OS as one of the following terminal types mentioned in the Universal Serial Bus Device Class Definition for Terminal Types (URL): . All terminal types under table 2.4 under section 2.4 (Bi-directional Terminal Types) . All terminal types under table 2.5 under section 2.5 (Telephony Terminal Types) . Communication speaker (Code 0x0306) Speaker or set of speakers designed for voice communication in table 2.3 under section 2.3 (Output Terminal Types) Note that this fix only helps if the user plugs in the USB device *after* the fix has been applied to the system. If the device has already been plugged in, installing the hotfix does not go back and remove it as the preferred audio device. In cases where the device has already been plugged in, the user would need to go to the control panel and change the preferred device back to its previous setting. Thanks, Richard Fricks Program Manager Windows Audio From: wdmaudiodev-bounce@xxxxxxxxxxxxx [mailto:wdmaudiodev-bounce@xxxxxxxxxxxxx] On Behalf Of Mike Dey Sent: Monday, April 02, 2007 11:02 AM To: wdmaudiodev@xxxxxxxxxxxxx Subject: [wdmaudiodev] Vista default audio We have USB handsets and phones for Voip. Is there any way to let Visa NOT SELECT our device as default audio right after installation? This is requested by many of our customers. Thanks! Mike