Lucifer Morningstar wrote in
:


On similar lines I was using a network cable that was way
longer than needed and the excess was coiled up.
At 1 gigabit packet loss was around 50%.
I replaced it with a much shorter cable and no packet loss.

That one is easy. Gigabit eathernet is very sensitive to interference.
Having the wires coiled like that very likely degraded the line electrical
characteristics to the point that you were getting a lot of lost/error
packets. CAT5/CAT6 is very sensitive to proper conditions for transmission
and reception. It doesn't take much to degrade a packet to the point that
it is not decipherable at the other end.