Yesterday my Naim app prompted me that a firmware upgrade was available for my Unity Nova and I asked it to go ahead an upgrade. The Nova disappeared from the app and by the time I went to bed an hour later it was still not back. This morning it was still gone so I pressed the front standby button to bring wake it up and the Nova soon started emitting these loud slow pulsing noises such that I had to unplug the speakers. I then managed to have it on long enough to be recognized by the app. I looked at the firmware on the app which said it was up to date. Plugging the speakers back on and waking up the Nova just exhibited the same problem.
I did a factory reset and more worrying developments. Everything seemed to go OK initially though strangely the firmware version was still current and did not need upgrading! Once more, when I connected the speakers I again got the loud pulsing noises. There was then a crackling sound from inside the cabinet (like sparks we going off) and a faint burning smell.
A warning flashed on the front screen a couple of times but vanished too quickly for me to see what it was. I unplugged the power and speakers as quickly as I could. Later, I plugged the power back without the speakers and again got the crackling/sparking sound. Now everything is unplugged and I’m not sure what I should do!