Hi. I've been struggling with the MIDI CH button for months. Following the instructions in the user manual 2.6.1 just doesn't work. I have had lengthy email with Jose at Arturia support about it. He confirms Kelab only transmits MIDI on Ch 1 but I can't change channels using his instructions.
He's very helpful and responsive: this is what he wrote. Does it make sense to you?
"Well this is expected because all the MIDI Routing is done by the DAW, So if you want to use a specific MIDI Channel on the MIDI/Instrument Track and in the Arturia instrument, you need to select that Specific channel on the Track Properties and inside the Settings Section of the Arturia Instrument.
Then select the MIDI Transmit channel 4 on the KeyLab Essential using the MIDI CH button and the marked keys.
This will restrict that MIDI Track and Arturia Instrument to receive only Messages coming from MIDI Transmit Channel 4.
But if you put ANY on the Track and ALL on the instrument, then any MIDI Channel will be received by both the Track and the Arturia instrument."
If anyone knows how to get this pesky MIDI CH button to work, please let me know!