Hi, there is no note 70 or 71 on an APC-MINI MK2.
You have notes 0-39 (for the main matrix).
The bottom row (mute buttons) are notes 100-107 (left to right). The buttons on the right (top to bottom are notes 113-119. The shift is note 122 but doesn’t seem to have an LED.
Remember when looking at MIDI messages in the log window they are represented in Hex so 70H is 112 ad 71H is 113 if that is what you are looking for. Maybe that is why it is not working.
Also the MK2 sends and receives on MIDI CH1 for the bottom and right LED’s.
For the matrix LEDs it sends on MIDI CH1 but the returning MIDI CH will determine the brightness or blink rate of the LEDs.
Please review this post for my summary or go to AkaiPro and download the APC MINI MK2 Manual.
Steve Caldwell
Bome Customer Care
Also available for paid consulting services: bome@sniz.biz