Jitsi Meet - no video or sound for 1st participant

I am a complete newbie to Jitsi Meet and am having a problem. I can easily start a meeting. I then send the generated link to a 2nd participant via email. Then he successfully joins. His end works fine, He sees himself and sees and hears me. However, on my end I see me but do NOT see or hear him. All I see is a small, black window with his name in the middle. Does anyone know what I am doing wrong?

I am using the latest version of Windows 10 and the Google Chrome browser.
Thanks for any help you can give me.

I was able to figure it out myself: It turned out to be a Chrome extension called “Disable HTML5 Autoplay”. I removed that extension and Jitsi Meet now works properly. My suggestion for anyone having this type of problem is to try disabling chrome extensions one-by-one until you find the offending extension.