First post on a Naim forum....so bear with me if you would. I am not a qualified electrician so my comments are based on experience and may use incorrect terminology.
My experience with Naim goes back quite a while, to a Linn, Aro, Armageddon, 52, 135s, SNAXO, S-CAP, SBLs on Mana. Quite a complex system, which I sold some 20 years ago.
Back then I spent a LOT of time mucking around with tuning and optimizing mains supply and several of the most important points I learned were;
1. The system appreciated being fed from a single electrical source i.e. a single socket of appropriate rating
2. If the individual components are plugged into a power block in order to achieve this, it was essential that the block was of high quality and provided the exact same earth 'resistance' at each socket. A poor, high resistance earth on any single component resulted in major loss of performance.....adding harshness and removing the system's rhythmic agility and 'bounce'.
3. The cable used between hi-fi feed sockets and fuse board has a major influence on the sound. You need to use audiophile approved cable i.e. cable known to produce good sound, because some don't (for whatever reason) and will result in a hard, amusical sound. Using cheap power strips was similarly a recipe for disaster.
4. Mains cables are hugely subject to burn-in. I know this a contentious subject...but here's what I found. Whenever I fitted new 'improved' cables (component or supply) the sound would initially improve, then deteriorate markedly after a few hours and would continue to sound bad for week(s), before suddenly improving one day and maybe continuing to improve for a while. This caused a great deal of angst known as ppp, (post purchase paranoia). I got so fed up with this that eventually I rigged up a burn-in jig that allowed me to put power cables into a circuit with something like a fan, which I ran continuously for a week or more before installing the cable into my system. The good-bad-good effect disappeared completely, leaving just the upgraded sound. If I was replacing supply cable or any other component, I used to set volume levels then switch off, disconnect speakers, place them facing one another a few cm apart, reverse polarity of 1 speaker cable and play them for a week continuously at the preset volume (be VERY careful with the volume as its possible to burn out speakers if the volume control is increased, because in this set-up the actual volume you hear doesn't increase when the power to the speaker does). In this way I could play my system for a week continuously without driving everyone crazy. Doing this, I heard just the improvement, with no more break-in effect, which for me ruled out claims that burn-in is caused by gradual aural acclimatization.
Some of the cable I used between fuse box and hi-fi mains outlet never improved, so I know some cable is just bad, hence my advice to go with audiophile 'approved' stuff which is known to produce good sound.
5. Experimenting with mains supply and earthing is a very frustrating hobby, full of pitfalls, wrong moves, self doubts and extended burn-in requirements. Standard OEM cables, a power block optimized for hi-fi, a separately fused, appropriately rated mains supply using cable with proven sonic attributes and a high quality mains socket all properly conditioned (burned in) should be all that's required to achieve really good sound from a well matched, room optimized system. Keeping contacts clean should be the only maintenance required.