MIDI woes (part 1)

[Almost Aviation]

Okay, I am going to add a bit more to this. I have noticed something specific that helps (which I'll get to below), so maybe someone can understand what's going on.

Although I was initially assuming the NDLR is doing something wrong and then getting out of sync, I have noticed that the problem persists even after rebooting it (including removing the USB cable for half a minute). When I reboot it, it still seems to out of sync and sends baffling combinations of MIDI ON/OFF messages when I start/stop or change chords. I am interpreting this to mean there is something downstream of the NDLR that's actually going wrong, which in my case means something in my iPad setup. Now I do have quite a complicated setup hosted in Audiobus, a part of which is shown here:



You will see that this includes connections for each NDLR channel to a synth app, but also in each case to another parallel destination, which is actually another iPad connected over Bluetooth - I have highlighted this for channel 4, which is the NDLR Pad. (This is so I can also drive other synths on the remote iPad.) To cut a long story short, if I remove the Bluetooth connection for the Pad channel, or if I create a simpler setup without any Bluetooth channels, it seems to work properly.

I don't know why this is, but I guess there must be a technical reason that someone can make sense of. I am a beginner at MIDI but I have understood it is a non-handshaking (fire and forget) protocol, so I am guessing this is actually going to be something about some other protocol that's involved with how the iPads implement MIDI over Bluetooth.
I'm not sure if this explains why you are seeing it Ian, but perhaps this will ring some bells for you.