Hmmm - seems that cable discussions lead to a lot of controversy.
First of all adaptors will ruin the signal, so you need to get rid of the adaptor so hear what your expensive hi-fi is capable of.
But nevertheless - this is my experience, and I'd like to share it.
The source to preamp connection appears to my ears to be quite vulnerable, as that is where the signal can suffer some musical corruption.
If using a Naim source, Naim provide DIN interconnects, which are musically very good in a Naim context, i.e. rhythm and pace.
Once out of Naim sources, the temptation is to use slightly cheaper interconnects, which actually do sound OK, I mean you hear the clarity and nothing seems missing. a case of not doing anything wrong, but the problem one of not doing the Naim musical values particularly well either, in terms of engagement, rhythms and musicality. At the level of kit you got 282/250.2, these musical traits should be important to you, as this is what you paid a LOT of money for.
However Naim (and also Chord, and Vertere - to my ears, and I stopped there, maybe there are others) do specialize in keeping the musical and dynamic integrity of the signal, there is a lot more to cables meets the eye.
The musical signal is an alternating current which goes back and forth between the source and preamp, and the signal is modulated in that AC signal, so the job is a lot harder than it appears.
One of the quality features of Naim and Chord cables particularly (I don't know the inner secrets of how Vertere do it) using a non compression clamp on the plugs which doesn't squeeze the cable and change the impedance. There are many details and all together make a big difference musically to my ears.
In short - if you want to really hear what your expensive kit is capable of, I found that indeed, use a Naim cable, or failing that due to non-availability, use a chord one like clearway 3.5mm to DIN, or a Vertere one if they will make it for you. It doesn't really matter which one, as they all sounds slightly different or quite different, but Chord and Vertere (as I said I didn't test others) do understand what makes the Naim sound. I think Vertere make a 3.5mm to 2 RCA cable which actually is really fantastic for the money (maybe 70 GBP?), but of course a 3.5mm to DIN cable could be even better.
the musical gains are totally worth it in terms of rhythms, Dynamics, proper tonality, musicality and sheer engagement.
Don't try to save money at this critical part of your system, it's only 80 GBP maximum for your Chord Mojo interconnect.
My experience, my ears, my system, YMMV, etc etc etc, just trying to help.