Polycom SoundStructure C16 Design Manual page 507

Are the microphones unmuted? Can microphones be routed to the amplifier (lower the gain at the
crosspoint!) and the microphones heard in the local room?
Check that the wiring for the remote virtual channels on the wiring page matches how the system is actually
wired.
Feedback Elimination Doesn't Seem To Be Operational - Feedback Can Be Heard Locally
Ensure the feedback eliminator is enabled on the microphones being used for reinforcement as shown in
the following figure.
Also ensure the sound reinforcement signal path is selected at the matrix crosspoint. There should be a light
blue background on the crosspoints routing the microphones to be reinforced to the audio amplifier as
shown in the following figure where "Table Mic 1" is routed to the "Amplifier" virtual channel.
How Do I Enable Auto Gain Control Or Noise Cancellation On The Program Audio Material
And Video Codec Audio?
Customizing SoundStructure Designs, in the Processing Noise Cancellation section, describes how to
select the Line Input "ungated" type, and then how to use that signal processing path in the matrix. Once
Polycom, Inc. 507