SPDIF audio devices are not displayed in Microsoft Office Live Meeting audio/video wizard, however you are able to select it in Office Communicator.

To solve this issue you can set the following registry key:

To add this key by using Registry Editor, follow these steps:

• Start Registry Editor (Regedt32.exe).
• Locate or create the following key:

on 32bit client:

HKEY_LOCAL_MACHINE\Software\Microsoft\RTC\DeviceSettings

on 64bit client:

HKEY_LOCAL_MACHINE\Software\Wow6432Node\Microsoft\RTC\DeviceSettings  

• On the Edit menu, click new, select DWORD (32bit) and type DeviceCategoryMask and then press ENTER.
• On the Edit menu, click Modify.
• Type 0x1FF, and then click OK.
• Quit Registry Editor.
• Restart the office live meeting to make the setting active.