cant hear any sound during a meeting, not me , not the participants

I'm sorry you are having audio issues. I would start here. 1) Make sure the audio is working on your computer. Watch a YouTube video. 2) start a Zoom meeting; no need to invite anyone. Click the arrow up by mute/unmute and Test Speaker and Mic (see screenshot). See if that works. If still not working, 3) I would also unplug and plug back in your headset if you wear a wired headset. 4) See if the computer mic and speaker work if the headset doesn't work. If the computer mic and speaker work, but the headset doesn't work, it is the headset. Finally, I should have mentioned this to start, but I'm assuming you did try this, is restarting your computer. 

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