Two strips exactly the same running the same code, one flickering random LEDs?

Other Hardware LEDs and Multiplexing
1

I recently had delivered a 5m WS2812B strip and have been testing a small 15 LED strip for a few days while my 10A supply turned up, all has been working fine.

I wired up the new 10A supply today and ran the DemoReel100 example and I instantly knew something was wrong, flickering all down the strip, some parts were just solid color some were flashing. You could see it was performing the loops but it was just messed up.

Anyway, after a couple hours messing around I decided to wire up both my test strip and the main strip exactly the same, with the same code running (15 LEDs) and see what happens. It's no where near as bad as what happened with the demo but theres still random flashes of different colours.

I've posted a video on YouTube so you can see what's happening, they're going the opposite direction because the strip is the other way round but it's running the same data on both. The top strip is my test strip which works fine and the bottom strip is the one failing for some reason, look towards the left of that strip and you'll see what it's doing.

Any ideas?

EDIT:
If you change the playback speed to 0.25 on YouTube you can see it's actually lighting up quite a few LEDs more than you can see at full speed.

2

Here's an idea. Why don't you read the forum guide and provide the things it suggests, instead of relying our psychic abilities?

3

Are you wired as seen here?

800×469 135 KB

4

Can you isolate the problem to one strip?
Can you provide a hand-drawn schematic of how the strips are connected?

5

larryd:
Are you wired as seen here?

800×469 135 KB

Thank you, this was my problem. I had everything connected properly, using a capacitor and resistor in the right place.. I forgot to connect the damn ground wire from the arduino though.

Thanks a million!