Blue Iris

I have BI setup to create a new file every hour, but recently it started creating short 10 second files that can't be played.
Screenshot: https://imgur.com/a/DXZtcAU
What is happening here?

I’ve seen other reports of this.

Do the short clips occur at the cut over period for the hour? I’m wondering if this occurs when BI would start a new clip but the cam triggers at that exact point/time?

Yes it happens when it creates a new file at the hour mark, or a few seconds before.
The files are unplayable.

What happens when you right click and open containing folder? Does it go to a BVR?