Hi all! I’m having an issue with a new Blue 2-1 switch that I have installed to replace a Lutron dimmer switch. When I turn the switch on at any power level locally at the switch I have no issues. When I turn the switch on remotely (i.e. with Home Assistant, Zigbee2MQTT, etc) at a power level over ~15% the light will flicker and produce a loud humming / buzzing noise. It only happens when remotely controlled. I’ve turned the switch on and off 100+ times to try to reproduce it and can’t make it happen when using the switch directly/locally.
The Blue switch is setup in as a single-pole dimmer. Replacing a single-pole dimmer.
I’ve tried a Red Dimmer switch in the same spot and it does NOT do the flicker/hum when either locally or remotely controlled.
The outgoing switch was a Lutron MA-600. This appears to be an MLV-compatible leading edge dimmer, same as the Blue switch.
The fixture is an Elco Lighting EL1499ICA 12v transformer which supports MLV-compatible dimmers, per the spec sheet.
The bulb is a single GE EXN 12v 50W MR16 halogen bulb. I have more of these bulbs hooked up to Red Dimmer switches (with no issues) but this is the only one that I have hooked up to a Blue switch. I’ve tried 3 other models of halogen bulbs and 4 models of LED bulbs (8 bulbs total) all with the same result.
I’ve tried tweaking min/max levels and ramp time with no change to the issue.
Any advice on what might be causing this flicker and hum when I control the dimmer remotely?