3.The Remote option is used to send/receive Control Surface commands. i.e, the transport controls, the knobs, and the faders. (see Custom Assigning Controls for more on this)
To use the knobs, faders, and transport to control Ableton turn Remote On for the 1st input. This will route these messages into the software enabling you to use the knobs, faders, and transport to control different functions in the software.
By default they are assigned to their best controls already. If you have the knobs or faders assigned to midi port B on your MPD or MPK then you would turn Remote On for input 2.
If you would like to use another controller via the MPD or MPK’s MIDI in port then turn Remote On for input 3. To route Control Change messages through the MIDI out port on the MPD or MPK, turn Remote On for output 2.
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