|MadSci Network: Physics|
I have never had an experience with phenomena anything like this. The fact that it is so predictable in time rules out animals. Since it is loudest in the kitchen is there any possibility that it comes from the water pipes ? Is it possible for you to turn off all the power to your house ( using the main breaker ) just before 11:55 ? Does that affect the sound ? If not, does turning off the main water valve just before 11:55 make a difference ? Do you have timed water such as a sprinkler system ? Let us know if we can help you, with a followon question. Gus
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