Bro, is there anyway to overcome this issue? im facing the same problem as well. Kinda irritate that i need to switch back to dumb mode in order to keep the LED work fine… thanks.
Not that I am aware of. But this happens only when the mapping is changed, so it is a pain in ass whilst you are configuring your mapping but once you are done you should have no problem.
you mean once you finalized your mapping, you do not need to start in dumb mode everytime? Thanks.
I mean once you finalize your mapping and restart the APC and Traktor you should have no problem, but you still have to start the APC in dumb mode every time.
oic… aite thanks for the advice, muchly appreciated! 
are you guys using the other banks? Like why go into “dumb mode” if your only going to use bank 1? If you stay in regular mode all you have to do is make sure the “Master” Track selection is left on and you can map away never having to go into dumb mode. Iono do what ever feels right for you.
do u mean whenever i startup the apc40 and traktor, i have to make sure it is in MASTER track so the lights will auto be there?
Ok. say you start up traktor and you have your apc40 in regular mode. When it starts up the APC40 “Track Selection” light is on Track one. Just select the “Master” in “Track Selection” and map away. Everytime you load up Traktor and your APC40 you just have to have the “Master” re-selected and your APC40 goes back to your Mapping Template you made. All lights will work, led feedback and knob halos go back to normal.
Now here is something to think about. In this mode you actually have additinal banks to work with but IMO APC40 offers more than enough to map in Traktor. Let me know if you need a video made to explain a bit more.
Video explanation… and below is my apc40 map demo.
Your “MASTER” mode on startup does actually work wonderfully. Even thou i did not map my midi mapping in “MASTER” selected, but it still works when “MASTER” was select before Traktor starting up.
my mistake, from start you should map everything with the “MASTER” tracker selected, or else problem like LED malfunction might happen. I have to redo everything again now, sigh…
glad to help. feel free to ask Q’s for any future mapping needs for apc40 or djm900 stuff. That’s the gear I have. So can help as much as I can.
LED output
I hope this offer hasn’t expired
The issue facing me is caused the APC40’s inability to “ignore” an output’s OFF state, instead choosing a second output’s ON state, both outputs having been mapped to the same LED inside the APC’s clip launch grid.
For example,
First, I map a single button’s LED to 2 duplicate Outputs, both being Add Out > Loop Recorder > BeatPosition. (This output can be used to create a 4 beat metronome, but I am am trying go one step further by creating a 16 frame visualizer where each frame, consisting of a 5x8 pixel grid, changes with every beat of a 16 bar recorded loop.)
I assign Output A to be green on the second beat of a 4 beat loop [Controller range = min 0.25 - max 0.50, Midi range = min 0 - max 1].
Then I assign Output B to be red on the fourth beat of the loop [Controller range = min 0.75 - max 1.00, Midi range = min 0 - max 3].
As the loop recorder plays, I want the LED feedback to be: no color, green, no color, red. That’s unfortunately not what happens. Only one output is received by the APC and the other is lost.
Help?
so the problem isn’t the apc40 at all then but the midi that traktor is sending to it? only way to be sure would be to dump it using some app i guess. i thought that traktor was sensible enough that if it had two conflicting values for a single ‘out’ midi message (as u have) that it would choose the higher non-zero one. the order u add in’s and out’s can also matter in some cases - not always tho.
you’ll need hrtbrkd for any actual apc40 issues but here’s some midi dumps from the 2 controls u have setup. first is when using different cc’s for each of them (each line(s) repeats a bunch of times)
* [traktor ] b0 01 01 [] type=cc name=CC001 value=1
* [traktor ] b0 02 00 [] type=cc name=CC002 value=0
* [traktor ] b0 01 01 [] type=cc name=CC001 value=1
* [traktor ] b0 02 01 [] type=cc name=CC002 value=1
* [traktor ] b0 01 01 [] type=cc name=CC001 value=1
* [traktor ] b0 02 02 [] type=cc name=CC002 value=2
* [traktor ] b0 01 00 [] type=cc name=CC001 value=0
* [traktor ] b0 02 00 [] type=cc name=CC002 value=0
and then when combined (which works as u would expect given the output above):
* [traktor ] b0 03 00 [] type=cc name=CC003 value=0
* [traktor ] b0 03 01 [] type=cc name=CC003 value=1
* [traktor ] b0 03 01 [] type=cc name=CC003 value=1
* [traktor ] b0 03 01 [] type=cc name=CC003 value=1
* [traktor ] b0 03 02 [] type=cc name=CC003 value=2
* [traktor ] b0 03 00 [] type=cc name=CC003 value=0
so it’s cycling between 0 and 1, then staying at 1, then cycling between 1 and 2 and then just sending out 0 (which it does for the longest amount of time)
i haven’t messed with the loop recorder out’s too much - but i guess you have some debug to do and has nothing really to do with the apc40 and everything to do with traktor.
edit: traktor is just sending out 0 from both controls 50% of the time, for the first half of the loop recording
hmm.. looks like I still have a lot to learn. Thanks for the reply. I’ll have to come back and decipher it once I know a bit more.
btw had another quick look and i had ‘blend’ ticked. without blend ticked… instead of sending out 0, 1, 0, 3 it’s sending 0’s, then pairs of 0+1’s, then 0’s and then pairs of 0+3’s. so when u want the led to be on the apc is going to be getting lots of 0’s at the same time. in theory it should sort of look how u want but the led’s will flicker. i’m sure i’ve missed something obvious and remember now why i never map directly in traktor but do all this logic in midimasher 
i’m sure the solution is simple tho and someone who knows more will chime in…
I’ve found Bome’s MT to be a solution, although it feels like a step away from a simplicity. I’m still looking for the easiest way to make Traktor choose output A’s ON instead of output B’s OFF.
I’ve downloaded at installed midimasher, but it’s learning curve is too steep for me. I wasn’t able to find a centralized tutorial; just random tips inside thread posts scattered around various websites.
bomes might be your best bet. the only way to do in in traktor is to use modifers to mask the values u don’t want - but u can’t have a modifier change it’s value from an OUT in traktor - u need something external to make it happen somehow.
this is a problem… i think i need to come up with some kind of simpler config file format that covers most bases and then people can use lua for more esoteric stuff. some tutorials would also be a good idea ofc - i just haven’t had the time. i could write the code u need - but if u have bomes already doing it then no point really.
All I’ve managed is to make it work on one LED, and just that was a bit tedious to do. I appreciate your offer to write the code but I’d prefer to learn how on my own. That tutorial on the other had is a wonderful idea.