Polycom SoundStructure C16 Design Manual page 361

The SoundStructure VoIP Interface
Once you've confirmed a SoundStructure VoIP Interface is part of the config-
ured devices installed, check the Edit Channels control to ensure you have a
SoundStructure VoIP Interface designed into your project. While the channel
names may be different in your project, in the following figure, the virtual
channels "VoIP In" and "VoIP Out" are seen as defined in the system.
If you don't have the VoIP interface input and output virtual channels defined
in the project, using the Edit Channels control select a VoIP Interface, click
Add, and close the Edit Channels control. Use the File > Save option to save
your file to ensure your new channel definition will survive a power cycle.
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