Geolocation is not perfectly accurate and it will often place you in a nearby area as narrowing it down to your city/suburb is gathered by geolocation companies from a number of data-bases. This article from What is my IP discusses this further.
Line attenuation calculations for ADSL will differ from those on FTTN. If you have a central filter, you can test if this is affecting your speeds by connecting the modem into a different telephone socket in your home. Central filters work by separating one socket from the others specifically for ADSL. These are installed (and removed) by private technicians.
High attenuation can be caused by a number of possible causes such as a fault in the network, an issue related to the internal cabling.
- Shelly