Red dimmer in 3 way flicker/strobing

Hey guys - hoping I can get some help… I recently picked up three red dimmers and got around to attempting to install them. I am in a relatively new home less than seven years old everything has neutral. I installed two of the dimmers in single pole configuration with neutral and they both seem to work fine, minus some humming when I put my ear close. The major issue I have is with my three-way installation in my kitchen. I believe I have everything wired correctly as per the three-way with a dumb switch with load in the box.

My issue is that when I turn them on or off the pulse continually. Even when they are at their 100% brightness they continue to pulse, occasionally they will even turn off, until I power the switch back on again. The dumb switch and the three-way are working correctly in that they can turn the lights on and off independently, but the pulsing is always there. Interestingly the buzzing/humming coming from it seems to fluctuate at the same frequency of the posting of the lights.

The exact same dimmer switches in a single pole configuration controlling the exact same LED lights in my ceiling have no issue, it is only this one in a three-way configuration that behaves this way. Any ideas? I’ve checked all my wires are tight, and I think the wiring is correct. I have the correct device handler in smart things and it’s configured correctly for three-way with a dumb switch. The switch is reporting in the app only 33 whites so it seems well within the operating limits, not to mention the same switch in a single pole configuration works flawlessly.

I tried to capture the behaviour in a video here https://drive.google.com/file/d/1Dv6O6vaNOOw5FycEcr8jPRpu6ZVFFuad

Does it strobe across the entire dim range or just as you approach full brightness? Lights shutting off by themselves often indicates your max brightness setting is too high.

The entire range. I did see lots of threads about setting max brightness to 80%, so I tried that before posting. Still the same, in fact any brightness I set it to it strobes (have not confirmed they shut off by themselves on lower brightnesses however). You can see if the video (if you’re able to view it) that the lights are strobing the entire time they are turning on/off.

As I noted as well - the exact same dimmers (red dimmers) controlling the exact same number of the exact same ceiling lights in single pole configuration have no issue from 0-100% brightness.

What is your parameter 22 set to?

Also, the Load is in the dumb switch box, right?

Load is in the same box as the dimmer - so i used:

P22 = 1

Strange since the same lights in the 2-way work fine.

One thing you could try would be to wire the 3-way temporarily as a 2-way, Take the 3-wire ot of the equation. Reset P22. I’m not really sure what’s going on but it would be an interesting test.