Unrelated directly, but we have had issues with household LED bulbs where they have been used as replacements to standard incandescent.
They have a tendency to flash occasionally when switched off. The rate varies from room to room. One room 34 seconds, another about 80 secs. Just a sudden flash. Contacted Western Power (distributors) and after the engineer checked all was as it should be with the line installation, said that it could be caused by a tiny feedback through the Earthing system that charged the internal capacitor of the individual bulb which then discharged in one flash. Not the sort of thing you want in a bedroom!
So, sensitive indeed, and in a different application.