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Inconsistant speed. Do you see anything wrong?
When did inconstant speeds begin? Did you add any new equipment...hammer a nail into the wall...notice any construction in the neighborhood?
The attic can be a central location for the Primary Feed into your house to distribute the signal. Any gear in the attic?
There has been no changes in or outside my house but there are new houses being built within 200 yards of my house. A basement was dug about the time the problem started.
You've got connectivity so I doubt the digging had severed a wire. Perhaps damage to your neighborhood node or pedestal.