Hi, i ran the 4.2.0 update on my prine 4+ earlier today.
I cant say for sure it caused the problem but ive since tried to play on it and the audio is not coming through the mixer at all. Im getting no audio through headphones or master. The tracks are loading and playing fine. All dials, sliders and switches are in the correct position.
Im dreading this is a send back to denon thing as im supposed to be playing on it at 11 pm 
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Anyone had this since the update or ever?
Any fix suggestions?
Did you try downgrading back to the firmware it was on before you did the update? I’ve had one funky update that I had to reload again for it to work properly but that was around V1.6.
Maybe downgrade and upgrade again? Engine sometimes doesn’t like a big jump in version numbers as there’s occasionally some mixer and control surface firmware updates that appear alongside the Engine OS updates. This updates the hardware (not the usual software update).
Sometimes it’s not clear when these extra updates appear. They can appear after an Engine OS update and they look like they slow down the interface for a few seconds before rebooting a second time. You just have to leave it for a bit after a firmware update.
There was one around V4.0 or 4.1 when Bluetooth was introduced.
Hopefully you got it sorted before your gig. Going forward I’d probably aim to do any updates early in the week if you’re a weekend DJ as any issues can be picked up before any gigs. I’m guilty myself of doing it close to playing out as I like to live dangerously but I know I’ve got a backup should stuff hit the fan. Let us know how it went and if you got it sorted.
Ah turns out its a warranty job. Getting sent to denon next week 
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