Although unable to offer an explanation explanation for this effect we have observed it.
As a result we mark our cables and interconnects for orientation.
Speaker Cable: -
this is marked with arrows. These point FROM the amplifier TO the speakers.
It is probably a good idea, early in the cable's life, to make some additional differential to, say, the amplifier end. This is because the markings can fade with age. I would suggest marking the plastic case of the speaker plug. Tippex or similar.
***See notes in "How to solder NACA5"***.
Signal Leads: -
HiLine - lighter grey strain relief insert at the signal source end.
Naim signal interconnect - collar around cable at the signal source end.
SNAIC carrying signal & power - collar around cable at the signal source end.
SNAIC supplying power to CD player - collar around cable at the CD player end.
Burndy carrying signal & power - collar around cable at the signal source end.
Burndy supplying power to CD player - collar around cable at the CD player end.
It is always a good idea to consult your Owner's Manual for additional guidance.
For "signal source" - imagine an insect (the signal) following a path along the cables FROM the source component (CD player, turntable, Tuner, etc.) through the preamplifier, power amplifier and ending at the speakers.
For information on case fuses (those fitted to directly powered units):
"If the kite safety mark is embossed on the edge of the of the fuse's conductive cap the fuse value should point towards the bottom of the fuse holder.
Should the kite mark be embossed on the very end of the fuse's cap then the fuse value should face the top of the fuse holder."
Naim UK Sales.