Keep A Journal
It is a good idea to keep a journal of any unusual and unexplainable things happening in your home or place of business. Jot down unusual and unexplainable things when it happens, where it happens and who was present as a witness. It is also useful to note the weather conditions: rainy, windy, etc. This will provide a possible pattern for us to check.
Remember: the weakest Link is stronger than the best memory!