[wdmaudiodev] Re: Vista default audio

  • From: "Mike Dey" <mdey@xxxxxxxxx>
  • To: <wdmaudiodev@xxxxxxxxxxxxx>
  • Date: Tue, 3 Apr 2007 11:45:30 -0700

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

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