The Global Mute feature is designed for handset/headset users. If you share a connection with your teammates to your counterparty, when you select that line with your handset, your teammates will not be able to hear that conversation anymore. The conversation will only be you and the distant end firm. If your teammates also jump into that line on their handset, they will then barge into that line and be part of the conversation.
For example, Pete and Melissa both work at ABC Trading. They have a shared connection with Jack and Molly at XYZ Securities. If Pete toggles to his handset to talk to Jack and Molly, Melissa will no longer hear the conversation. If Melissa also toggles to her handset and barges into the line, she will now be part of the conversation again.
A user that has Global Mute enabled is indicated with a handset icon to the right of their name (Figure 1):
Figure 1 Global Mute
Note: If you have Global mute enabled and want to disable it, please contact your internal IT team or Cloud9 Support at email@example.com