So just an update. Yesterday i received the level shifter so i integrated it into the system. Also redid some of the wiring and also added another 5V line towards the mid point of the led strip to get better current flow and voltage towards the end of the strip.
Seems now everythinig is working however i may have some more calibration to do but that isn't a led stripe problem anymore.
Thanks all for your help!
I have absolutely the same problem
so sir, how you fix it? just adding the level shiffter?