Troubleshooting an NAD D 3020?

Anyone have any experience troubleshooting one of these guys?

I picked one up today that is not behaving properly. When plugged in, the amber power light turns white, as expected; lights on front panel blink a few times as expected; then the power light turns red briefly, then goes back to amber.

When holding down the "Bass EQ (SERVICE)" button in the back, which should supposedly put it into service mode for the purposes of re-flashing firmware, instead of the lights on top turning on, the lights on front turn on instead, which is not indicated as expected behavior by the manual or firmware updating instructions.

It's also not obvious how to get the thing open. It appears it's held together with plastic clips, but I can only relieve tension on one of the edges.. I feel like I'm missing something, and likely to break the cover if I proceed.
 
NAD D3020 V2 will not turn on

I have exactly the same issue with a brand new unit that worked perfectly (great sound with no issue whatsoever) for about 6 hours, using either optical input from Oppo Bluray player or Bluetooth input. The next day, when trying to turn it on from the remote or by tapping the amber light on top, the front display flashes 3 times, then switch light on top turns red for less than a second and then back to amber, in standby mode. I cannot select a source. I tried this many times with sources on or off. Factory reset by holding Bass EQ at the back does not solve the problem. Unplugging and replugging the amp did not help either. Anyone else had this and found a way to fix it? Thanks.
 
This is a very compact digital audio amplifier and if any work needs to be done on it it requires a SMD soldering station .


I have found a large number of complaints about the amplifier online mostly relating to the digital electronics .Have a read of this link as poster "Robca " provides a PDF on it which might be of some help -


Help repair a D class amplifier NAD D3020 V1 - Page 1


Yes I know its not a V2 but some hints might help.


I should add repairs to this product will require more than basic electronic knowledge but maybe somebody will help you along.
 
After leaving it powered off for over a year, I decided to take one more stab at this yesterday before giving up and throwing it in the trash. To my surprise, it powered right on! And I played music through it for a few hours, through USB and Coax digital in.

Then I turned it off to plug it into a different outlet, and it did the blink -> red -> amber cycle again. Unplugging everything from it and powering it back on got it back to working again. I figured I would just leave it powered on forever and enjoy it that way!

This morning I tripped a circuit breaker, interrupting power to the outlet it was plugged in to. And now I cannot get it to turn on again at all (keeps going to Red). I swear it decided to work just to taunt me.
 
The failure reminds me of my Dayton SPA250 plate amplifier that it has automatic shutdown when it does not detect music (audio signal) in the output after a while .....

Maybe that NAD has that built-in function?
If so, you probably have a relay associated with a capacitor that goes into discharge and cuts off the AC supply.
It is to save energy when the user falls asleep on the sofa listening to music .....
 
Hello.
I replaced power transistors board.
45 eur .
 

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