Taking into account your anal nature it suprizes me that the water gods have placed you in the barrel on your own home.
Since i know you followed the crews and anything that didn't pass the white glove test was addressed personally, i too am dazed and confused.
Could you have a leak in the main before the house? What about backflow? Is the supply copper or pex?
pex moves a lot, even when strapped firmly.
Could debris be in the line?
Have you placed gauges on spigots and bibs to measure pressure when flushing, done a meter check or purchased a buttload of beer? I have a feeling a lot of brewskies will be consumed before this puzzle is solved.
Best of luck kiril
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