Trying to bypass the distributor here can be fraught with hazards. I would need the Naim RMA or I might be able to find out something with the serial number. Probably best I message you.
I live in modern well cared for Stateside condo development and did extensive renovation including costly dedicated wiring at advice of Naim dealer. The development and surrounding area periodically experienced short-lived power failure without outcome to my system or appliances.
In recent failure lights repeatedly and rapidly went on and off. During most intense moment I checked on my system and smelled what I would characterize as electric fire and saw smoke rising between my two Naim Fraim towers. Fearful of fire I unpluged my Naim recommended Audience outlet.
I live far from Naim dealer and dealer’s tech was going on holiday, but before leaving walked me through test of my system. All of Audience’s outlets worked and all Naim devices and all power supplies 500, 552 & 555 had Naim logo light-up. The speakers also gave a sound/thump when 500 came on and also made sound when my beloved CDS-3 was started, though no music came through.
Although I was walked thorough Naim’s setup for 552 and could get green lights to move around I couldn’t get anything to result in music.
I’m patiently waiting for my Naim dealer’s tech to return and have no intention of dabbling with system.
My question to anyone willing to speculate are the systems components likely to be in working order if Naim logo light-up and would logo light if fuses failed? If fuses failed would they produce smoke? All thoughts welcome.
Fallstaff
That’s very unfortunate. It the fuse blows there is no power at all to the device, so no green light.
(If any boxes have no light, it’s simple enough to remove the fuse from the fuse holder on the back of a Naim box, right next to the power cord, and replace it if it has blown. There is normally a spare in there as well, so you can insert that. But I guess this is no use to you right now.)
Suggestions:
1- check the output settings for the CDS3 and make sure these are set for what you’re using (i.e. either DIN or RCA – not both). Sometimes a power-down can re-set these (instructions cut in below).
2- when you say moving green lights, do you mean in Programme mode (source) for the 552 or just the face lights on the front? It may be simply worth moving the interconnect from the CDS3 along the row at the rear and see if one works? (assuming not done already?).
The case fuses with Naim kit (at the rear, flap next to the mains connector) are very small and I don’t think would produce smoke, as they are quite sensitive.
6.4 Output Socket Selection
A pair of RCA Phono output sockets are fitted on CD player
rear panels to provide an alternative to the preferred DIN
socket. Proceed as follows to select the RCA Phono sockets.
With the player stopped, press and hold the remote
handset disp function (handset in CD mode) or, if fitted,
the player disp button until the CD player prog indicator
flashes. Further operations of the disp function will now
cycle through each combination of the two socket types
(DIN only, RCA Phono only or both). The selected option is
indicated on the CD player display as shown below.
Socket Option Player Display
DIN O
Phono oo
Both (big)O 00
Press and hold the disp function a second time to exit from
socket selection mode.
To avoid compromised sound quality, do not select both
unless their simultaneous use is unavoidable.
Wow thats shocking! - if the power pulsed on and off it could drive the torroidal transformers to consume allot of power over a longer period of time (normally a torroid transformer draws allot of power for half a second or so). The equipment itself is fused - literally it could have been the power cords suffering…as for no sound it looks as if something has been ‘spiked’ - as Mr Happy has suggested this may have put your 552 into some weird mode… I would think the only thing would be to substitute working equipment in stages to isolate the problem - a dealer should be able to get to the bottom of this… Hope you have a friendly insurance company!!!..let us know how you get on.
Chris, thank you for clarification update on green light, your thoughts and suggestions much appreciated!
Happy, thank you for your guidance. I’ve tried 552’s manual for socket selection regretably my poor vision and trimerous hands suggest I wait for others. The moving green lights were attempt on 552 for programing. I’ve not gone near CDS-3.
Richieroo, my Naim tech had same conclusion try substituting and concern about power cord. If I’m correct you do not think toroidal transformer failed. I have homeowners insurance and my condo has coverage, but can’t do anything until professional assessment has been made. My fear has been having to trash one or more power supply.
Thank you for your insight and suggestions.
Please do check the CDS3 set-up as a first step.
Fingers crossed, it might be something this simple.
@Richard.Dane – Richard, ever seen Naim kit having a fag? – see above!
Bear in mind that the poster with the issue is in the US, that may not read quite how it would to a Brit. 
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The 500PS does have internal (non user replaceable) fuses, if any of these were blown, I’d expect the thermal trip to shut down the 500PS after a couple of minutes. These would produce an almost imperceivable amount of smoke.
Here’s my guess, the 500PS & 555PS have banks of discharge resistors, when the unit detects the AC has dropped out (unit switched off), transistors switch in the discharge resistors to ebb away the capacitor charge in a controlled manner in order to avoid nasty speaker noises.
If something damaged those transistors (such as rapid AC cycling) & switched in the discharge circuit while AC is present, lots of current would flow through those resistors & that would cause a lot of smoke & smell.
If my theory is correct, the problem unit should be very easy to pinpoint using your nose.
Regards
Neil.
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That sounds plausible … yeah that area of the board would be smell allot…having momentarily shorted a heavy duty project psu … things get mighty hot very quickly…and the offending area was easily identifiable…with evidence of some excessive heat…even though it was not damaged. This was an error on my behalf caused by a whisker of solder…(beginners error!!!)
Neil, sounds like you were living in my home!
Your description of AC cycling followed by smoke and lingering smell is precisely what happened.
If this is correct can resistors be replaced by Naim and NAP 500 salvaged?
Thank you for your insight!
Fallstaff
Yes……but by Naim, please do not let anyone else open up and mess with it…….its a very complicated amp, particularly the head unit. Hope it can be sorted by the US distributor.
Gazza, thank you!
I would only work with Naim dealer, I hope US distributor are in position to assess and repair.
Best,
Fallstaff
Hi Fallstaff,
The resistors in question are designed to dissipate the charge within the capacitors after the rectified wall socket power has been removed. If they have been subjected to current only limited by the transformer, the damage would usually be pretty catastrophic resulting in extensive PCB damage.
A replacement board is the only fix.
PCBs for both 500PS & 555PS are currently both available.
But let’s not jump the gun!
Have you identified the source of the smoke?
Regards
Neil.
Neil, I rely upon my Naim retailer’s tech whose on holiday and will return in few weeks, at that time he will review everything and I’ll have to see what decisions I can or will make.
In all cases thank you very much.
Fallstaff
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Hi iNeil,
You were on target!
My Naim dealer visited, tested every component and only NAPS555-DR didn’t work, when removed from Fraim smell of something burned was palatable. Dealer’s sending component to Naim North America don’t know if they can repair or will send Salisbury.
Best
Fallstaff
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Spooky! 
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