Sometimes, the particle stack gets corrupted on the SSD. Running a “Check particles” job does not show any problem, so presumably, the SSD copy is bad. It would be great to have the option to also check the stack on the cache and the option to refresh it.
Or perhaps an extra toggle next to the “Use SSD Cache” option saying “Refresh particle stack on SSD” with default value False. It would force a re-sync of the particles.