I have a problem with audio and/or sharing my webcam?

webinar.net Network and Firewall Configurations (Ports, Domains, and IP Addresses)

Below are the requirements before going live as a presenter:

• Presenters must have a minimum bandwidth of 15Mbps download and at least 5Mbps in upload.

Your connection speed is not the only factor. You have to also look for connection stability aka the number of people connected to that same connection. The connection stability will impact the number of packets lost during a webinar. Therefore, try to use Ethernet over Wifi and ask your team to not saturate the network.

• You must use Google Chrome or Firefox to share your screen, webcam, or audio. 
• Check your microphone and webcam on your browser settings. 
• Check if your camera/microphone permissions are allowed.

Google Chrome

https://support.google.com/chrome/answer/2693767

You can verify that by simply clicking on the lock icon to the left of the address bar.

Firefox

https://support.mozilla.org/en-US/kb/how-manage-your-camera-and-microphone-permissions

Click on the site identity icon (the lock symbol) in the address bar.