IIRC there’s an option for embedded scenes to recall something on a remote surface. I can’t remember if it can go across MixRacks, though. If it can, I suppose you could create scenes on the monitor surface which only mute and unmute things for you. AFAIK, there’s not a way to remotely trigger mutes directly, though.
It might be possible to trigger scene changes with MIDI over TCP/IP. That’s not something I know much about other than MIDI over TCP/IP is a thing that the dLive supports, so I’m afraid all the advice I can offer there is to search the forums.
Lastly, the worst option, at least in terms of cost (the other two are free), is to get a GPIO module for each MixRack and wire your buttons to both sets of inputs. I’m pretty sure it works like that, but you should read up on it and ask someone who knows what they’re talking about before spending almost $2k on a couple DX boxes.
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