I was trying to find the photos - do you have a link to the forum post?
In the process of searching, I found this thread which makes some sense, except that without a second Naim component (beside my amp), there appears to be no signal earth point? Adding the CD player appears to provide this.
I had a really helpful call from Naim support, who suggested similar, but interestingly a support call from a Chord team member, who loves his own personal SuperNait3 suggested the following fix:
“I can confirm that taking a ground wire and running from the post on the rear panel of the Naim and then making a connection from there to underneath the cover cap for the Power Amp in socket (that is to say, making no contact to the Qutest at all), results in a dead silent amp here. No, I have no idea why.”
Care needed to avoid touching contacts, or better, affix wire with caps in place. The slightest contact cures the hum totally.
Again you’re just connecting signal ground to mains earth. The ground post on the SN is connected to signal ground. The outer of the DIN socket is effectively connected to the chassis of the SN and so to mains earth.
Yes, indeed, but a very quick and simple fix. Some thin cable with a little spring in it, connected to then earth and then sits under tension wedged nicely to the power amp in sockets. Crude, slightly ridiculous on a £3,500 amplifier, but incredibly quick / simple. It suggests to me that as this is not an exclusive problem with just one third-party device, there perhaps needs to be a permanent and elegant solution in the next generation of products?
@MMky It would not be professional for another organisation’s support team member to comment on a Naim product. He clearly knew exactly what he was doing.
I also had the ground hum problem when connecting my Chord Qutest to the RCA input of my Supernait 3. The problem was fixed very quickly by my dealer who provided me with a link cable connecting the outer casing of a din connector to the outer case of an RCA. This used an input but provided the grounding required for the RCA. Since then I have got a chord clearway RCA to DIN cable, this has offered an alternative and more elegant solution to the problem.
Make sure the ground switch is set at default (chassis) on the ND5XS2 and keep the setup you have now with the Qutest connected to the SN2. Put your existing Lavender interconnect that came with the ND5XS2 back in (ND5XS2 DIN output to one of the DIN inputs on the SN2) as well.
Unfortunately I sold the original DIN cable so I can not try this. Is there a picture anywhere of how a single cable from ground pin to mains socket would look like? Or would it help to turn off all boxes, and reconnect and plug in again?
I unscrewed this plug, and now I can not screw it back in. Should I have squeezed the wire between this screw and plug? I can not feel anything in that hole to tighten it back any more. I am stressed out now.
Now I feel dumb. But thanks, i think you are right. I saw a picture here without that knurled knob and screw so i thought both needed to come off. I provisionally managed to attach the wire. Hum is gone, now it is only a soft buzz. But I will go to the dealer for repair and a permanent solution. Not my day today