Identifying USB accessory causing 'USB Accessories disabled' error on Mac

I realize there is much written about this issue but I can't figure it out. I have changed nothing on my Mac for years...No additions. All of a sudden, I constantly get this error message:

USB ACCESSORIES DISABLED: Unplug the accessory using too much power to re-enable USB devices.

I'd be happy to disable the offending device but I have no idea which one it is nor how to find it.

At a loss. Any ideas?

[Re-Titled by Moderator]