1. Press the < under the main fader to bring up the quick panel.
2. Press the Mutes button. This brings up the mutegroups menu.
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3. Select the channels you want to be in a particular mute group.
4. Press the Save button at the top of UC. Mute group buttons 1-8 will begin to flash.
5. Select a mute group. It will highlight.
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6. When pressed again, the mute group selected will unhighlight and the selected channels will unmute.
See the UC Surface Reference Manual, section 7.2 for more details.