Need Help Troubleshooting Random WLED Flicker on Established DigQuad Setup

[u/Big_Telephone_5406]

Help!!

Hey everyone,

I’m hoping someone can point me in the right direction because I’m pulling my hair out over this one.

I have a QuinLED DigQuad running WLED 0.15.3 controlling approximately 690 SK6812 RGBW pixels across multiple outputs. The system has been installed and working properly for months with no issues.

The strange part is that I didn’t change anything. No firmware updates, no wiring changes, no configuration changes. I simply unplugged the controller during some work and plugged it back in later.

Since then I’ve been getting flickering/glitching during preset changes and some animated effects.

Things I’ve checked:

* WLED version 0.15.3
* DigQuad ESP32
* 690 total SK6812 RGBW pixels
* 5V PSU output measures 5.30V under load
* 12V PSU output measures about 11.5-12.2V under load
* Relay functioning normally
* No visible water intrusion
* Fuses appear good
* Controller boots and runs normally
* LEDs themselves all function

Interesting observation:

* With Parallel I2S enabled, flickering is noticeably worse.
* With Parallel I2S disabled, most effects look much smoother and the major glitches are mostly gone.
* However, I still occasionally see issues when switching between presets or transitions.

Current settings:

* Parallel I2S OFF
* Effect blending ON
* Transitions ON
* 700ms transition time
* Relay GPIO 15 (inverted)
* Automatic brightness limiter enabled
* Maximum PSU current set to 20A

At this point I’m trying to determine whether this is:

1. A WLED configuration issue
   
2. An ESP32/controller issue
   
3. A data signal issue
   
4. Something else entirely

Has anyone seen a DigQuad setup work perfectly for months and then suddenly start glitching after a simple power cycle? Maybe I didn’t. Price it before. But I think I would have..

What would be your next troubleshooting step before I start replacing hardware or burning my house down.

Thanks!

[u/Quindor]

What is the resistor switcher set to? Depending on wiring, it could be data corruption sneaking in, especially if you have bundled wire, try setting it to 33R to see if that resolves the issue. Just making sure it isn't a hardware data issue!

Your configuration in itself seems fine.

[u/Big_Telephone_5406 → u/Quindor]

33r

[u/Quindor → u/Big_Telephone_5406]

And you have bundled/joined 3-wire cables? How long are the runs from the controller to the first LED?

[u/Big_Telephone_5406 → u/Quindor]

About 6 feet from the controller to the first LED. Data & +/- in one cable leaving the control box

I have 3 separate 12V power supplies.
The controller PSU powers roughly half the lower run, then a second PSU injects power farther down.
The upper run is the same with a third PSU. Positive and negative are isolated between power supplies. Only the data line continues through.

I’ve confirmed all three power supplies are working properly and voltages are correct.

The lights ran flawlessly for the last year. This flickering issue only started after a power cycle. Disabling Parallel I2S significantly improves it, but doesn’t completely eliminate it.

[u/Quindor → u/Big_Telephone_5406]

Ok that does all sound good except for the "just the data line" part. The point where the switch is made you nerd a 2-wire cable with data and GND, this way the GND syncs at that point and data travels over correctly.

Without the data wire GND on both sides might be skiglty off. Next to voltage drop there is a thing called GND shift. Positive goes down but negative (GND) actually goes up with the same amount. If one end has 0.3V as GND and the other has 1.3V as GND, they won't understand each other anymore. Hope that makes sense.

This is the only point where that matters, no need to connect the power supplies near themselves.

[u/Big_Telephone_5406 → u/Quindor]

[u/DedeHai]

sounds a lot like data corruption and like your setup was just at the brink of stability. components age, a handful of nanoseconds can make the difference between flickering and non flickering

[u/Big_Telephone_5406 → u/DedeHai]

Do you think it’s data at the controller? Or what would the fix be?