I had a problem last night with mine on 4.2.9.1. After the nightly compact/repair database event, BI lost the ability to record events. The events show up in the timeline as Alerts images instead of actual recordings. I checked in the clip folder and sure enough, nothing there between the compact/repair event and when I checked on things in the A.M.
I ended up having to reboot my system because BI wasn't opening the UI to check on things. I run as service as of right now on Win 10. I will look again tomorrow in the A.M. and see if it has done it again.