There's a few scenarios can cause a HR (High Resistance) fault.
For example, dry/poorly soldered joints on PCB boards (such as routers/line cards in the fibre cabinet), poorly terminated wiring at any point from the fibre cabinet through to your data extension socket, overhead wires rubbing on tree branches or the like, damp or corrosion on the D-side cables (again, from the Cabinet to your premises).
It depends on the severity of the HR as to the severity of the action DLM takes against your circuits connection, by applying stabilisation/correction factors.
Kitz has outlined above a method for ascertaining how severe the HR is ...... a well-developed HR fault manifests itself as a crackling noise on the landline phone, and causing umpteen transmission errors on your router, and more often than not a subsequent loss of connection altogether. It doesn't sound like you have that particular level of HR ??