First of all, the menu “default num of LED” doesn’t have anything with your problem.
How many LEDs did you set for the menu “Num of RGB LEDs”?
If you set it right(16), I think it is mainly due to bad soldering(Yes I know the PCB was out with presoldered.)
Could you check the soldering of the last working RGB LED and the first non-working RGB LED?
(In your case, 11th and 12th RGB LEDs)
If you are not able to check the state of soldering, then send me an email(flashteker@gmail.com)
Thanks.
Hojin.Yi
Thanks
Hojin.Yi