Red dimmer issue, secondary switch in 3-way is unreliable?

I finally got my new VZW31-SN (red dimmer) switches installed and configured, but I’m noticing an odd issue in cases where I have a 3-way setup with two dimmer switches. New construction, so both switches have neutral.

Toggling the light from the primary switch works perfectly every time. However, toggling the light from the secondary (non-load) switch only works about half the time. I can tap the switch to turn the light on, the LED bar fills up to show it’s lighting up… but the light never turns on, and the primary switch is still off. I can tap it again, despite the LED already being lit up, and that second attempt will usually (not always) get the light to turn on.

I’m using Home Assistant and zwavejsui, and in the zwave configuration I have group associations between both switches, for groups 2, 3, 4. I also have parameter 59-2 (forward remote commands) enabled on the primary switch but not the secondary. I followed this guide to get them configured.

I assume the problem isn’t packet loss, since I have the same 3-way configuration in two rooms, and both show the same unreliable behavior only on the secondary switch. But, that’s just a guess on my part, I don’t know how to measure z-wave network issues or what to even do about it.

Am I missing some other setting for this?

Do you have parameter 59-1 (forward local commands) enabled on both primary and secondary? How is your Z-Wave mesh looking?

Do you have parameter 59-1 (forward local commands) enabled on both primary and secondary?

I just double-checked, but yes, both switches have 59-1 enabled (which was the default).

How is your Z-Wave mesh looking?

As far as I can tell, everything is fine there. Nothing is marked as dead, and the network graph shows both switches with green connections.

Looking at statistics for each node, there are a small number of “Dropped RX”, but no more than any other node I look at. Nothing listed for “Dropped TX” for either.

It almost feels like the command was sent but ignored… but that doesn’t make sense either.

Are you in dimming mode or on/off mode? I remember running into a couple of 3 way issues when testing the beta switches if that was mismatched between the two.

Are both paired at the same security level? Association messages won’t be accepted by the destination switch if not.

I double-checked the dimming mode and security level for both, and both match.

Both have parameter 158 set to 0 (Dimmer), and both list S2_Authenticated security.

I appreciate the troubleshooting!

Unfortunately, I’m all out of ideas at this point. Let’s see if someone else can figure it out!

After doing some searching online, I’m starting to wonder if the problem could be my Z-Wave controller? I’m still using the old HUSBZB-1, which is 500-series, whereas the new switches are 800-series. I’ve ordered a Zooz-800 to replace my controller, maybe I’ll get a better result with that…