In that case, its not surprising that its picking up noise.
EO cables normally start out as large pair cable. Then they are split off in different directions at joint boxes. Those in turn can be split off ever more.
You could be at the end of the chain, with just a small number of pairs serving your neighbourhood.
Its more than likely there are faulty pairs with perhaps one wire disconnected in a joint. That means there is a good chance of poor transmission.
If you has a router which displayed the frequency distribution, you would probably discover some parts of the spectrum carrying few bits of data, where there is probably an interfering source. If you look at the Kitz site, there is a better description.
Do you know whether Openreach are planning fibre? If not, you may find an Altnet offering to provide fibre?
One thing you can do to make best use of your connection, is to eliminate unwanted content like adverts, which take up valuable bandwidth.
I use Pi-Hole as a DHCP and DNS server, and its very effective. I use a Raspberry Pi 3B, but you can run a version on a spare PC.
It applies filtering to all devices connected to your Internet connection.