If you can find a way to reproduce I'll be able to investigate a bit further. Enabling the texturecache.py logfile (@logfile=tc.log) would allow comparison of the kodi.log timestamp with whatever texturecache.py is doing.
Texture Cache Maintenance Utility: Preload your texture cache for optimal UI performance. Remotely manage media libraries. Purge unused artwork to free up space. Find missing media. Configurable QA check to highlight metadata issues. Aid in diagnosis of library and cache related problems.