Hi Jacob and welcome to the forum!
What you are asking would require some programming in GrandMA if you want your LED state to truly depict what GrandMA is doing. GrandMA has the capability to do LUA scripting which is beyond the scope of what we support on this forum. Also I believe GrandMA has a “midinote” command, that you could use but probably not to the level of what you are trying to achieve.
With that said, if you want to “guess” what GrandMA is doing by incoming MIDI messages from your MIDIMIX, we could indeed program LED behavior as you wish within Bome MIDI Translator Pro. It just may or may not be an accurate representation of what is happening in GrandMA.
If this is what you want, I can provide an example of what you describe.
Let me know.
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