Inconsistent Midi triggering from external controller

HI I have a second hand APC 40 and a Korg NanoKontrol
Using Midi Monitor I can see that ALL the buttons send midi note on/off messages from both controllers BUT when trying to detect those midi notes in VDMX, for instance to select a clip in the media bin or trigger a preset, some of these same buttons and their midi messages are consistently never received in VDMX - they do not register or be detected .
Hope that makes sense, and that Im not imagining it !!! and that there is a simple fix or that there is something I am doing wrong somehow… Thanks for any confirmation and or solutions… Paul

Are they both enabled in the VDMX Preferences > MIDI > MIDI Settings?

yep most of the buttons and all the sliders are actively working just some of the buttons -do not register even though midi monitor shows they are sending a note on and note off message- thanks for reading

Are the notes that are not working sending some sort of additional program change, or changing the layout?

Maybe pull up Protokol and see if it shows some other commands: Protokol | hexler.net

Thanks Great Tip_ I will see what I can make of it. Cheers