Getting weird filter/blur effect

I've been using zoom to take remote music lessons for about a year.  This past lesson I was in a new house/room, and I noticed that part of the screen is blurred and the affected area changes as I move around. I have no filters or effects, and I've never seen this before.  When I'm not holding the instrument the background is a bit out of focus.  When I hold the instrument, part of the instrument is out of focus also.  

This is running Zoom Workplace on an iMac (macOS 15.6.1) , and I get this effect on both the built-in camera and a Logitech C920S. Behind the camera is a big window, and it's a cloudy day.  Yesterday it was sunny and I got the same effect.  I'm including links to screen grabs on my google drive (I hope that's OK) of just me and me with the bass to show the effect. Any ideas?

https://drive.google.com/file/d/1wb8JT40CzWbWehD0VCvN--La--oMi5I9/view?usp=drive_link 
https://drive.google.com/file/d/1-Ps15okCYlVFnGBHJsN1dk7AHpDNuzBZ/view?usp=drive_link