So I contacted Denon support the other day to get this resolved but I was just sent a PDF of the authorized service centers and denied warranty repair as it’s been past a year since I bought it. (I bought it in November 2018).
Now, under normal circumstances, that would be understandable. However, seeing as this is a common issue, as evidenced by the following topics:
I stopped using the mixer for a few months then plugged it back in to do the update few months back forgetting i had the issue and it worked for a few weeks then the crackling started again the last few days.
Honestly, I’m surprised they don’t already know what the root cause of the issue is. All our mixers have the exact same symptoms. Unless Denon/InMusic isn’t aware of this issue… which wouldn’t bode well for X1850 owners.
I will update in a few weeks but hopefully this has fixed it, if your unit is in warranty and you are able you are best off sending it to Denon to fix but if its out of warranty or you are unable to send it this could help you. There is probably a better, less bush fix solution to this by beefing up the grounding at other points but if this works it should be fine.