I have over 30 2n1 VZM31-SN’s, with about 2/3 in dimmer configuration and 1/3 in relay switch configuration. All are connected to neutral. Firmware date: 20240412; Firmware version: 2.18; Driver date: 2025-10-01. Connected to a Hubitat C8-Pro, exposed to Amazon Alexa through Hubitat (hunches are OFF in Alexa).
Starting a couple of months ago, units that were ON randomly turn OFF for a couple of seconds, then back on (I haven’t seen OFF to ON events). None of this is by Hubitat or Amazon Alexa action that I can see. The problem is getting more frequent: twice today on the stairway light and once on the entry way light. The wife is getting annoyed.
Since I saw the entry way light cycle from ON to OFF to ON, I quickly captured the log (I’ve only been tracking non-ordinary log items, so only 2 entries):
When this happen, I assume it happens on all your lights together? Does your C-8 Pro’s Zigbee network go offline at the same time? (The logs should show that.)
This is not a systemwide phenomenon. This is individual units cycling off to on while all other lights around it are stable, including lights on the same circuit. I’m not seeing any evidence that the hub is going down, but I will have to double check that.
Ok, that’s good! I had an issue where one of my switches was crashing and bringing down the Zigbee network with it. Seems like this issue might be different then.
When that one switch crashed, it caused my other switches to turn off and back on.
I think so. I’ve not been able to see all of the LEDs in time to notice if changes have occurred, but twice I’ve seen the LEDs’ light up all yellow when the OFF-ON transition occurred. Is that the color of a reboot cycle?
I think it goes through solid color (whole bar) teal then blue then yellow when it reboots.
Most reboot situations we’ve seen on the forums tend to be caused by power issues. I know you mentioned that you have neutrals connected to all of your switches. Are you seeing that represented in Hubitat (sorry I don’t remember the parameter number off the top of my head but it should show you neutral or non neutral)? Sometimes, the neutral wires end up loose when installing the switches.
Other possibilities could be a power surge or potentially a misbehaving load. What sorts of lights do you have connected?
The lights are all dumb LEDs, different brands (mostly CREE BR30’s and GE 60W eq. “regular” bulbs). For example, the entryway has 2 chandeliers with 4 60w GE’s each, the stairwell is 4 CREE BR30’s (may be BR40’s).
I have a very hefty whole-house surge arrestor tied to the mains panel.
Other loads on the same circuit don’t even flicker when these events happen.
Any idea what this log entry means: “BASIC_CLUSTER Unknown Attribute:null”?
I had this problem when I had a heavily loaded Zigbee network with a bunch of Juno Smart Wafers that were not playing nice and working correctly. I experienced random reboots of the Inovelli Switches (not all, and not at the same time), but of course you noticed it when the lights went out momentarily and you look at the switch and see the yellow blue Ukranian flag color reboot sequence on the LED Bar.
This happened both on a smartthings hub and a Sonoff Zigbee Coordinator.
Once I got rid of the Juno lights about a year ago, that made my Zigbee network stable and I haven’t seen it happen ever again!
I just started to experience this problem with the Blue 2n1 switches as well. New behavior…after they were exposed to Alexa via Home Assistant. Haven’t yet tried to remove them from Alexa to see if that corrects the issue.
Another possible data point: the entryway lights have blinked OFF then ON several times today. The last two times I was able to check the events, and BOTH times the blink correlated with an energy report – despite parameters 310, 311, 312 all being set to 0 (which I thought would disable energy reporting entirely) :
energy 87.03 kWh Entryway Lights Main Dimmer IB 11/26/2025 6:03:35.497 pm
New data point: An energy report just [caused] coincided with my entryway soffit lights to blink (they are on a different IB unit, set as a relay switch, than my entryway chandelier mentioned just above):
Looking at this I want to clarify the color meaning during boot. If you see yellow during the boot sequence it means the neutral is detected and if you see green no neutral was detected. You will only see one of the colors (yellow or green) during the booting of the switches. Sorry I should have been more clear in my earlier reply.
