Zooz ZEN30 switch intermittent load triggering

The ZEN30 (FW 2.1.1 HW 2.0) is on a 14 node (all Zooz) compact network close to the Zooz ZST3R-LR stick on a USB extension, Zwave JS integration. No problems with other devices.
A simple automation toggles the connected dimmer load when a Zooz ZEN34 remote switch paddle is pressed. Operation is intermittent sometimes waiting 5+ seconds between presses helps but not always. Monitoring “zwave_js_value_notification” events confirms HA sees every paddle press.
If the automation is changed to toggle the relay load it works every time, just an issue with the dimmer.
I also notice that:

  • both dimmer and relay loads can be toggled using controls on the device properties page in HA as expected, however operating the ZEN30 manually does not change the state of the controls as expected.
  • there are 3 controls on the device properties page but the first appears to do nothing (except log an event it was toggled), second and third operate the dimmer and relay loads respectively. (Zooz support said the first control was a master switch operating both loads, but I’m not seeing that)

I was previously using this device with SmartThings without issue. After excluding/factory reset/including several times I’m running out of ideas. Does anyone have any suggestions?