Extremely loud spontaneous electric noise NS3

[Cliftonhanger]

Hi there I’ve seen some threads about the Stage 3 making electrical noise near guitars and other amps, but I think I have a different issue. My stage 3 88 works fine for about 5-10 minutes and then is interrupted by a sound that I can only describe as sounding like a big power surge electrical noise. As if it’s been struck by lightning. Touch any key on the keyboard and it simply makes this loud buzzing sound. I power down and power up and it starts right up again. However, if I unplug everything (power, headphones, channel 1 out) and then plug back in the problem is “solved.”
Or it is for another 5-10 mins and then starts up again.
Has anyone heard of an issue like this? Does it sound like it’s among the issues I read about the nord power source?
Any thoughts or advice greatly appreciated!

[pterm]

Hi Cliftonhanger, welcome to the forum.
The behavior you describe does not match the pathology of the other known Nord power supply issues.

My best guess is your supply has a soldering or component failure that appears when the temperature of the supply rises. I assume that after 5-10 minutes something on the power supply expands due to the temperature rise and causes an open circuit. Based on your description a failure at one of the rectifying diodes or one of the large filter capacitors.

I recommend contacting American Music and Sound (Nord repair/support for North America) as you likely need a replacement power supply.

I hope it goes smoothly.
-pterm