DVR storage shrunk?

Recently our DVR went from storing dozens of recordings at ~75% to 14 recordings at 100%.

The stream app shows that the DVR is full at 14 recordings. The recordings are mostly 35 minutes long.

Also much of our DVR self deleted when this 100% usage started.

We did upgrade to a new set top box. DVR was the same and working for a few weeks after the upgrade.