I bought a custom “neon sign” made with led strip. It came with a bluetooth led controller and a corresponding mobile app. The strip is a 3 wire version vcc, gnd and data. I tried to connect the strip to WLED and I am seeing a flickering of random colors. Video attached. I tried different versions of LEDs WS281x, TM1814, 400kHz in WLED.
Did not try UCS8903 and TM1829 as that would require flashing newer firmware on a pre flashed device.
What are my options to figure this out?
You would need to know which IC the LEDs use. 
Otherwise, keep trying the supported types. Note that it may not be supported.
Also possible it has embedded patterns in the LED chips like some of the Govee lights.
What happens when you just apply power but no data?
Other usual suggestions about common ground between data supply and power supply, levelshifter,etc.
@divsys The LED is off when no power.
When the config is set to WS281x 400khz (normal is 800khz according to docs), the colour is set to the correct one but some flickering still exists… Effects don’t work, crazy flickering.
So I am thinking that I should reverse engineer the bluetooth controller. May be I need a oscilloscope which I don’t have.
I tried the Hz setting in the multimeter, Here is what I found
Original bluetooth controller:
Solid color ~781 kHz
Effects ~ 739 kHz
The wled Controller: (the one I want to use)
Solid color 6.8 kHz
Effects 100 kHz
This is same for all the settings ws281x, 400kHz, etc
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What am I missing?
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That means apply only V+ and Gnd to the LEDs NOT data.
Only connect 2 of the 3 wires.
The leds are off
So the quin data boosters solved the problem…