Polycom SoundStructure C16 Design Manual page 276

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12
The first step to creating the wireless microphone's reference is to build this
reference by creating a new submix called "WirelessRef" as shown in the fol-
lowing figure.
The AEC reference for the wireless microphone is assigned to the new submix
as shown in the next figure.
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