I added a high end Ethernet cable which feeds my Aurender. The claim was that this cable minimized noise, but I believe that the N20 input is galvanically isolated, so in theory, the expensive last few feet of Ethernet cable should have been a waste of money, but at the time I thought it improved the sound. I’ll need to replace it with a cheap cable and see if it makes the same difference after I have lost my return privileges.
BTW “snake oil” is the mother’s milk of politics and it has been used to control the masses for thousands of years. So, a bit of audio snake oil is more amusing than a serious issue.