I have been using a new MC6000Mk2 for a few weeks now and have notices a static noise from the controller. It is not present when the controller is not connected to the sound system but is there as some as it is connected.
The sound is present when nothing is plugged into the controller (no inputs connected). I am using balanced cables and have tried a second set, so I don’t believe it is anything to do with the sound system or cables.
The Static sound is present on both the XLR and RCA main outputs.
It is not a ground loop, I know what they are and how to deal with them.