The hum at the demarc pretty much points to an issue before the drop.
I would continue to open trouble tickets with Verizon Repair. Repeated tickets should trigger upstream cable work, most likely at the slick. 🙂
Verizon should be repairing OSP copper if no real company alternative is available. In the town I live in, Verizon rolled out Fios back in 2007/8. I am an early adopter.
The company retired the legacy Bell System OSP copper. People with problematic telephone lines were given the option to migrate over to Fios. Our three POTS lines all developed noise towards the end. Once all were switched to Fios, the noise problems went away. 👍
