Back in the dark ages before Ethernet was invented, I worked on a LAN technology called Cambridge Ring. It used a phase locked communication over two twisted pairs. We tried to run it between two buildings about 1/2 mile apart connected by a CCTV multicore cable running in a duct. After a LOT of experimentation we discovered that for reasons of minimising cross talk the video cable pairs had different rates of twist and were consequently of a slightly different length. We inserted an extra 1.5 metres in one of the pairs, and hey presto it all started working.
And now back to your scheduled programme.