Don't waste your time, put DJii footage profile at once (codec, bitrate, container,...).
Anyway to give a piece of answer here, it's probably* connected to "core video", the API connected to quicktime which deals with video frames. Once corrupted, it may also be for other tasks out of Resolve.
* This is only my personal opinion.
Now, since I don't know High Sierra, you could :
- first go inside Resolve preferences and switch between OpenCL and Metal to check wether it has any influence;
- anyway give BMD's team your logs here