So I wrote the KANE QuNeo Mixxx Preset, and after extensive testing, I have encountered what I believe to be some problems with the QuNeo's LEDs flickering. (QuNeo firmware v1.2.24, bootloader v1.3)
Here's are my steps to reproduce the problem (transcribed from my github issue):
1. make a print statement which triggers only when the right vertical arrows are sent a midi message
2. load up mixxx from a terminal (so prints will show), load tracks into both decks
3. play right deck alone. note that the print statement is triggered continually (this is because the right deck's vertical arrows are sent LEDs based on the right deck's VuMeter).
4. play left deck alone. note that there are no print statements, yet the right vertical arrow LEDs will "pop" occasionally (as in brighten to almost full velocity), and all LEDs of the inactive deck flicker pretty constantly (including right vertical arrow LEDs).
I should note that although this case both isolates and highlights the issue, it's not the only case (the flickering seems to happen relatively frequently with regular use of the preset).
My conclusion is that the cause of the problem must lie with either the QuNeo or Mixxx. I think it makes a lot more sense for the QuNeo to be causing this than Mixxx (for one, why would Mixxx be sending phantom midi messages? for two, I hooked Mixxx's midi output to kmidimon and confirmed that there are indeed no messages sent to the right vertical arrows while the left deck is playing).
I am wondering if this issue is related to the large volume of midi messages being sent from Mixxx to the QuNeo. I connected many LEDs on the QuNeo to Mixxx's VuMeters, which means that whenever a deck is playing, Mixxx is sending gobs of midi messages to the QuNeo. They seem to be interpreted correctly save for this flickering issue (which, I might add, isn't the worst thing that could be happening...).
Thanks for reading; any and all help/insight is appreciated!