I've come back from holiday and my LEDs are flashing.

My LEDs have been fine for a few years, I came back from holiday today and now they're flashing weirdly. What is wrong?

Video of flashing

Log attached

I've tried with the app to set solid colours but nothing changes. The solid colours don't come on any of the LEDs

It is affecting from the first LED so I can't tell from what point it's potentially damaged.

To explain my setup, 2 of the instances are using the same LEDs and get switched when the TV is turned (activated by a contact sensor), one config for when the TV is facing the living room (the default) "Hyperion" and the other for when the TV is facing the kitchen "TV Turned to Kitchen" - this is effectively to change the colour correction when the TV is turned as one side is closer to the wall.

Both of these instances are affected because they are the same string of 75 LEDs connected to the Raspberry Pi

The other "Hyperion Xmas Tree" is a WLED ESP32 board is working normally.

I have a basic multimeter, Is there a way to identify where an LED may have failed?

This was all working fine up until last week.

The LED output of the 2 75 instances aren't on at the same time, this is happening when both are independently active.

But still happening when each are fully off.

No, the power was not turned off over the week, the power is always on to the pi and LEDs (independently) just the LED output is turned off when the TV is off, however it looks like the Pi crashed / shutdown at some point during this time.

All LEDs are receiving power

One of the instances is disabled at startup anyway, I have deleted one of the instances but I know this isn't what it looks like when both are on at the same time. This was all working completely fine for ages up until now.

This is what it looks like

My suspicion is that the first LED is faulty somehow and the data is not getting passed down the line but I don't know how to tell how many - it's awkward as this is the end with the connector and I'd have to cut them off one by one, and solder to find out

I have hooked up the wled board to the LEDs and they are all working normally on that

I've reinstalled the OS and only loaded up the one instance and all it's doing is flashing the first LED.

If I remove power from the LEDs, it crashes the Pi. I don't know if it's relevant, just info. Could it be something to do with the Pi as the LEDs appear to be fully working with WLED?

I have wired up the LEDs to the WLED board and chosen this as the interface source - this works correctly. The issue would seem to be with the Pi's gpio output is there a way I can test / fix it?