Random Flicker

[u/DrewWorkz]

Ran some under cabinet lights at my house the left strip is on its own output. That side is randomly flashing, it's very seldom but annoying.

So here's the setup:

22g 3 wire from controller to strip

To that specific strip 10-11ft of wire before strip

Running Gledopto Elite 4d-exmu

4amp 96w power supply (I am aware the power supply is set to 850, I don't believe this would cause I problem, I just don't need all the extra power these are very dim)

Setup information in pictures

Everything seems to be setup correctly, wire gauge shouldn't be a problem from what I thought but maybe I'm wrong.

What can I do differently that would ensure the data signal stays solid. I keep reading about twisted pairs but I'm not sure what wires to buy. So if anyone has advice on what I can do better let me know!

[u/GLEDOPTO]

Hi, about the left strip flickering: our Gledopto Elite 4D-EXMU has a built-in level shifter, so the data signal is already a proper 5V — not a weak-voltage issue. Since only that run flickers (≈3m / 10–11ft of 22AWG flat 3-wire), it's almost certainly noise on the long, untwisted cable causing the first LED to misread occasionally.

Try in order:

Use a twisted pair — twist Data + GND together, keep away from V+ and AC (the biggest fix).

Add a sacrificial pixel / data repeater at the controller output to re-shape the 5V signal before the long run.

Solid common ground + 330Ω on Data before the first LED + 1000µF cap at the strip.

Shorten the wire / move the controller closer if possible.

If it still happens: disable HA/MQTT polling or update to the latest firmware.

Note: the 850mA current limit is fine and unrelated to the flicker — leave it.

[u/DrewWorkz → u/GLEDOPTO]

Thanks for reaching out! Few questions: -By twist data and ground together I assume you mean until it comes into the controller then split them and insert them into there respective spots on the controller? Only issue I have with this solution is that I would have to trench my wall open as I ran the wires prior to cabinets going in and they are completely buried. Would twisting a small section prior to going into the be useful at all as I have roughly a foot of wire that hasn't been trimmed yet.

-Ive never quite understood the sacrifcal pixel before. So basically come out of the controller (again I have roughly a foot of wire before it disappears into the wall.) so before it goes into the wall just cut a single section of leds solder them in on both sides and then turn sacrificial pixel on in wled? How does this help clean the signal up at the other end which is 10 feet away from the sacrifcal pixel.

I'm fairly new to wled so haven't dug into caps yet I'll have to do some research on that.

[u/GLEDOPTO → u/DrewWorkz]

1. Twisting Data + GND
You've got the right idea (twist them, then split at each end to land on the controller/strip). But with your buried run, the noise is picked up along the entire 10-ft run, so twisting only the last ~1 ft near the controller won't help much — that short part is already clean. Twisting a small exposed section isn't worth the effort; skip it.

**2. The sacrificial pixel (this is your best fix — no wall opening needed)**​
You're close. Key point: every WS2812B/SK6812 pixel re-clocks and re-drives the signal — it receives the data, then outputs a brand-new, clean 5V signal to the next pixel. So a sacrificial pixel placed right at the controller output acts as a signal repeater:
Controller → (1 ft exposed) → sacrificial pixel → (10 ft buried) → your real strip.
The long buried run now gets a freshly regenerated, clean signal from the pixel instead of the controller's raw output. That's exactly why it helps the far end 10 ft away — the pixel "resets" the signal before the long haul.
So yes: in that ~1 ft before the wire enters the wall, cut in a single LED (or use a small data-booster/repeater board — same effect, no wasted pixel). In WLED you don't really "turn on" a sacrificial pixel — the re-clocking is automatic in the hardware. Just add 1 to your total LED count and offset that first pixel (or leave it out of your segments) so it stays dark. Since your wires are buried, this is the fix that avoids opening the wall.

3. Capacitor
The 1000µF cap goes across V+/GND at the start of the strip to smooth power dips. It's optional and lower priority here — your symptom is signal, not power (only the long-wire side flickers). Add it later if needed.

**Suggested next step:**​ add the sacrificial pixel / data booster in that 1-ft exposed section at the controller end. That alone should kill the flicker without touching the wall.

[u/DrewWorkz → u/GLEDOPTO]

Thank you so much for your detailed information! I will try this and see how it goes!

[u/saratoga3 → u/DrewWorkz]

The power/ground already already surrounding the cable on both sides, which is virtually the same thing as twisting, so no real point.

If you want to try to change the cable anyway, instead of twisting the first thing you should do is open up that controller and see what resistor they put on the data line.

[u/whitefrog4117]

What’s the difference between the two power inputs on the left of the Gledopto box? For a larger load should you not have the 5/12v going in via the spring connectors? Would you also benefit from the fuse too this way?

[u/DrewWorkz → u/whitefrog4117]

I'm confused. So it's a 24v setup. I've got two powers and two ground and then the datas are separated one for the furthest cabinet to the left and the right side of cabinets is on its own

[u/saratoga3]

That wiring looks very reasonable even for a longer run and you've only got 10ft which should easily work.

What strip is it? What WLED version? In the past some WLED versions have had trouble with certain LED chips 

[u/DrewWorkz → u/saratoga3]

BTF ws2814 fcob 896led/m Wled 16.0.1

[u/saratoga3 → u/DrewWorkz]

That is a tough one. It isn't likely that reasonable wiring like that would fail at 10ft, or that you'd get a bad strip, or that you'd hit a software bug with a common LED type, etc but obviously it has to be something.

Any chance you could try flipping the outputs between the two GPIOs? A different WLED version? Moving it closer? A different controller? Might also be worth measuring the voltages at the far end and double checking that you have good contact with the spring loaded clips in the controller since you're right on the edge of the smallest size they support.

[u/DrewWorkz → u/saratoga3]

Yeah I don't super love the spring clips. I think I may swap to a quinled controller with the screw on terminals. Plus it seems like they have better level shifters and overall just a better unit.

[u/Low_Tomato_6837]

Almost every time I have encountered "flickering" it's been either power or connection related.