So, you enter the class, and everything seems fine, but you can't hear your student! Don't worry. This issue is usually pretty simple to fix.
This article relates to situations where you can't hear at all. For situations where you can hear, but the audio quality is poor, then this article will be more useful for you.
Is the problem on your end?
If you can't hear, it's good to rule out the most basic possibilities first. It may seem silly, but it can happen to the best of us!
Is your volume turned up?
Are your headphones plugged in?
A quick and easy way to see if the problem is in the classroom or with your equipment is to open YouTube in another tab. Just click on the first video that pops up, and see if you can hear anything when it plays. If you can hear something, then the problem is in the classroom. If you can't, then it's with your equipment.
If you think your headphones are the problem:
Try plugging them out. If the sound works from your computer's internal speakers, then the headphones are likely the problem.
Next, try plugging in a different set of headphones. If they don't work, then you may need to change the audio settings in the classroom.
Could it be a microphone issue?
When a class participant speaks, the little dot in the top right of their video window will go green. If they are speaking, but the dot doesn't go green, then the classroom is not receiving sound from their mic.
In this case:
The participant should try unplugging their headphones. This can force the computer to use the internal microphone, which will solve the issue if their headphone mic is the problem.
If that doesn't work, then they may need to change the microphone settings in the classroom.
Other possible solutions:
Is the tab muted? Right-click on the classroom tab, and you should see the option to "Mute Site" or "Unmute Site".