Ok so i have a new 2019 Denon X1800 and a new RMX-1000 both are fully updated.
So here is the set up to connect a RMX 1000 to your Denon X1800: connect 4 1/4 cables to your Denon send and return. The Send cables go to the RMX input, the return cables from your Denon go to the output of the RMX. On the Mixer (X1800) go to your Utility settings/advanced audio/FX return enter. RMX says to set this at -10 don’t because it turns the Vol. way down on your signal. I set it +10 and it was close to my regular setting. Now exit the utility and turn on your BPM FX button on your X1800 and turn it all the way up 100% wet. Some say 10 o’clock but this is the volume control now for the RMX, and if you want to hear it and use all of its function you must turn up the Dry/Wet 100% or it gets washed out totally. The dry/wet is like the vol for your X1800 or (dry), And the Vol. for your RMX (Wet). Last thing some of us play in stereo I have the Bose F1 system and play in Stereo on the X1800. The RMX is a Mono based device and you need to change your button at the top of your mixer to Mono or you will only have one channel. Once this is done your RMX 1000 should work perfectly and completely.