Video Crossfeed

When I host a Zoom meeting one of the participants has an intermittent video problem.  He is using an HP laptop Pro model with a built-in camera (screen model 15-BW018CA).

A distorted black-and-white version of another participant's image flickers in duplicate across the top of his image (see attachment;  identifying info blacked out).  This appears on his screen and the screen of all participants.  After a second or so a different participant's image appears at the top of his image.  However, the problem never occurs when he turns off his video and transmits his profile image.

Any suggestions would be welcome! 

Thanks!