Resolve Idle, but disk activity high.

What is going on? When Resolve is idle (and ALL caching is turned off), the disk activity is high and I can hear the drive churning away on and on. I can see from the resource monitor that it is Resolve.exe reading from the drive, but Im not sure why. Can someone explain why it would be doing this if the caching is turned off?

Just some ideas. Maybe its rendering audio waveforms. If you have long video files with audio that can take a while depending hardware. If you disable waveform display you can check if it goes away.
Alternatively maybe thumbnails creation.