LED PSU causing flashing?

I have been trying to get two strips of LEDS working. A 12V WS2812b and WS2815 LED.

I have been trying to solve the flashing issue and no data signal so it was clearly the data line. Over a short distance either strip worked but when over a 2m distance they both failed.

I changed the wires to 20AWG from Cat6 as I read this was good practice
I’m on my fourth logic level shifter ,currenlty the SN74AHCT125 so I could boost the signal
I added a capacitor for the 5v power rated at 25v and 22uF
I added a capacitor to pins 1 and 14 on the SN74AHCT125 (Only had a 25v 10uF one not 0.1uF)
I tried using different MCUs (Heltec ESP32, Wemos D1 Mini ESP2866)
I googled and read everything and nearly gave up as nothing was working over the short distance…
I then tried swapping my 12v LED driver to a lower powered one that I was using elswhere to run one strip. Its only rated at 3A but Bam the flashing issue and data line problem was gone!!

My PSU is a new BTF Ultra Thin LED Light Power Supply DC12V 200W Transformer Adapter designed for LEDS. Is it faulty? Do I just replace this or are their any ideas on what could be cauing this?

Ive tried removing the Earth as a test but the problem persists. (Was thinking of noise)

I didnt think having more power was an issue as the lights would just draw what they need plus my final set up / design was 3 x 5m LEDS all powered from the one unit. Hence my choice.

Any clever ideas or bin it and go with something else??

Thanks in advance :slight_smile:

I checked the dc voltage with a multimeter and the BTF Uniy shows 11.76V whereas the small LED driver that works shows 12.6V. The 12V is also driving a converter to step down to 5V. Both outputs show 5.1V that powers my MCU. Not sure if this is significant or not but thought it might help.

All grounds are connected.

Changed PSU and issue sorted