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Upon starting/joining a Zoom meeting you will see this taskbar at the bottom of your Zoom window
'Mute' (left) indicates you have joined the Audio of the meeting and your Mic is currently on. (Click this to Mute your mic, but stay joined to audio)
'Start Video' indicates you have not joined video. By selecting 'Start Video', if there is a camera connected to the computer - you will be prompted to join Video.
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1) Select the caret symbol '^' next to the Microphone icon + 'Mute' button 
2) These settings allow you to change the devices (that are active on the computer) for Audio Input (Microphone) and Output (Speakers)
Note: If you do not see your desired device as an option this means the computer is not recognizing it. Please check its connection/power
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1) Similarly, select the caret symbol '^' next to the Video Settings to configure camera and video related settings.
2) These settings allow you to change the devices (that are active on the computer) for Video Input (camera)
Note: If you do not see your desired device as an option this means the computer is not recognizing it. Please check its connection/power
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Both audio input (microphone) / audio output (speaker) will use the headset
(2) Discussion AV Mode Setup
Audio input (microphone) will use the classroom mic / audio out (speaker) will use the classroom speakers
(3) Hybrid AV Mode Setup
Audio input → headset | Audio output → classroom speakers
Other Resources
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