What you do with the set of actions I described earlyer is fill in the midi map.
AFAIK the RM4 will just not react to anything that wasn't set using that method (since it doesn't know what the proper action is).
I think it's quite easy, just choose the PC you want, then use the actions I described to teach the RM4 which channel corresponds with that PC.
You will need to set the right midi-channel though.
There's no way of querying it, since the RM4 and RT2/50 only recieve and pass-through, they don't send anything.
What you could do is this:
- set up sets of 2 footswitches on you Little Giant: PC1 and PC2, each set on a different channel.
- use the actions above to teach the RM4 to respond to the PC's
- see if the RM4 reacts, the set it reacts with will tell you the midi-channel.
I personally would just rip off the top cover
There are around 25 screws, all of those on the top need to come off
and 3 on the front.
When looking from the front of the RM4: the most left and back screw, over the pre-amp tubes is a different type, so pay attention to that.
It requires a smaller bit and will screw up the other holes if you twist it in there!
(it's different because they didn't want a screw sticking out into the place where people will be sticking their hands to change tubes
)