Comment Line interference or impedance (Score 4, Insightful) 291
It's possible that if this all started while, or just after, they got done digging up the neighborhood to run the fiber, that they accidentally did something that is causing line interference or an impedance of some sort. In this case, a line technician would be able to determine an actual physical problem with any of the lines. Obviously, a phone call to have them check won't hurt.