I realised my post was about headphone volume not master volume, so I created a new thread so not to go off topic. My apologies for any confusion caused.
Hi everyone. I thought I would share this problem to see what other people think.
NB: I am intentionally exaggerating the speed of the headphone volume knob in the video being turned, so the crackling sound can be heard when recording it with a mobile phone away from the headphones - with the headphones on your head, the volume knob doesn’t have to be turned so rapidly to hear the crackling sound.
I’ve contacted Denon today and they kindly told me I only get a 1 year warranty for the DJ Prime …