Forgive me, this is only my beliefs. If you had so huge differences, it means it were problems of grounding loop and/or electric noise harmonics running on your cable. If all was instead already good, it's matter of endorphins and anything raises theirs production, takes to a good sounding feeling, so anything does that, it's welcome...Years before to expand and give Ethernet to two devices I was using a tp link sg105 v6 . I was wondering what is the fuss and I have connected it after my router and from that the Supra cat 8 to ifi lan silencer and WiiM pro plus . Indeed it seems that the sound is much clearer when this device is in between compared to straight connection .