I’ve had mine for donkey’s years but never understood, nor asked to be honest, the purpose of the balance knob. I would have thought that with any Naim or top-end system, the assumption would be that the listener was sitting in the middle of the speakers and so would not need to balance the sound.
For me, our listening space is asymmetrical. The right wall opens into a dining area, so it is shorter than the left. The Naim app allows me to adjust the balance when necessary. I guess I have adjusted to the asymmetrical nature of our space b/c I rarely use it.
Also your ears may not be even. Not every recording is balanced. And some people don’t sit in the middle because the room layout (or “decorating committee”) didn’t allow that.
I suffer from regular bouts of glue ear which affects my right ear worse than the left. I usually just shift to the right a bit on the sofa or send a Valkyrie to get up and alter the balance on the 32.5.
Stereo volume pots are rarely perfectly matched at the lower end of their range, and so a balance control can really help here. Furthermore, rooms and furnishings can affect the balance that is heard in the listening position, so again, the balance control really helps here. Lastly, recordings and sources aren’t always perfect, and age or wear to analogue source material can often cause an imbalance that a balance control can either partially or completely fix.