So my understanding is that disabling one of the folders from auto-import fixed your CPU usage issues.
Indeed. However, I had already tried that procedure at some point (see earlier in this thread) and identified a 'mixed web video' folder as triggering CPU loopings... Some 'unknown audio' files found inside were re-encoded which seemed to fix the issue, but it started again later... Strange enough, no new files had been added to that folder in the meantime...
Can we try to determine what auto-import was doing with that folder? Enable it and watch. Could it be analyzing audio?
As explained before, all files in this and all other folders in my library are properly imported incl. thumbnails, their data seems complete. Are there any specific data fields I might search to find missing tags...?
My import settings are:
Album cover download: disabled;
Audio analysis: disabled for both audio and video files;
Writing tags when analyzing: disabled;
Fetch movie & TV info: disabled;
Generate thumbnails: enabled;
Match up with external changes: disabled;
Repair invalid links: disabled;
Ignore files previously deleted from library: disabled.