Hi Nick, yeah i thought that with SSL, just with having the Denon HC4500 and the HC1000 i know that has the lights lit when you set cue points etc. When i mean the latched state, i'm referring to the likes of Enable in ME for the effects. So if i enable the text feature in ME for example, i need the button i've got mapped to stay on. What i have noticed is that i've got to use the likes of midipipe to allow the LED' to light up anyway, but what i've also noticed is that when i press a button, it comes up (via midi monitor) as note on and note off message. So i will need a button to 'toggle' on off. I've sent a support ticket to A&H asking if this can be done but waiting to hear back. I know under NI's controller manager software it can be done. Just didnt know if ME has the capability under the mapping to enable an 'output' as toggle, gate, note on/off etc for controllers that don't have software to change settings like that.