it can not install in my computer

My first two experiences were very good. No complaints on them. The next two times I was not able to hear the zoom meeting. I could not find anywhere to turn the sound on for them. I have a PC desk top and separate speakers. The mic in the lower left corner was not on the 3rd & 4th meetings. Only a headset, which I don't have. How can this be corrected so I can enjoy the zoom meetings?

It works and is easy.

This extension is no longer working on firefox. It won't let me schedule, and I'm using hte portal manually.

Triumphantly courageous! ~ Isoke...