Puzzled about MIDI export

Just exported an orchestral project to MIDI for mastering in Cubase, and I’m puzzled: the first seven instruments have their MIDI channel assigned; thereafter, there is one (Horn 3, bizarrely, not even Horn 1) that is assigned but all the other instruments show up as ‘Any’.

I notice, looking in MIDI List Editor, that for instance Horn 4 has its notes assigned to channel 5, but controller data is assigned to channel 4. That’s, uh, counterintuitive…

The channel and port information exported in MIDI files from Dorico should match what you see in Play mode.

That’s what I thought, Daniel, and what I’d expect.

On checking further, every instrument assigned to ‘Any’ that I looked at had controller data addressing a different channel to the note data. Sometimes the offset is one (11 & 12 e.g.), sometimes not. I noticed two percussion instruments addressed notes to ch. 10, whereas they were assigned to their own separate channels in the original.