There are 2 types of Webinar Zoom type, first participant allowed / can turn on/off the audio or camera icon below. In this type the audio volume in smartphone can easily turn up and down.
The second type, participants are passive, can not turn on/off audio and camera ( no icon below usually have hand wave icon ). In this type the volume is always maximum can not turn up and down except I cross the audio icon at the left top. I always use smartphone Xiaomi Redmi Note 9 Pro. I wonder this bugs is on the smartphone or zoom apps ?
Hello, My name is Brandon. Thanks for joining the Zoom Community! The default volume for participants of both Zoom Meetings and Zoom Webinars is controlled by the participants machine. The volume on the host computer does not affect the volume other than the ability for an attendee in a Webinar not being able to turn on/off audio (aka mute).
I hope that this helps.
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